The French Indochina War in Vietnam 1.0

Running through the years from 1948 to 1967, Campaign Series: Vietnam 1.0 will cover the three wars of the time period, the French Indochina War, the Vietnamese Civil War, and the first years of US involvement in Vietnam. And with 100+ scenarios, we hope there’s something for everyone to dive in.

We’ll start this new countdown to Vietnam 1.0 blog series with the French Indochina War. Here goes (with a disclaimer we are still with a late BETA version of the game)!

The French Indochina War in Vietnam 1.0

Rewind your clock back to 1948, as that’s where the French Indochina War kicks off in the battle of Giong Dinh. Here’s the Scenario Selection dialog with the current beta:

From the Sky – Battle of Giong Dinh

At Giong Dinh, it is still relatively low key, with a quick company sized jump to clear out a suspect Viet Minh operations center there:

French Paras at Giong Dinh

Looks innocent enough?

Building up from there, the battle of Mao Khe in 1951 is covered next. Defending Mao Khe is approximately a Battalion sized French formation against the elements of the Viet Minh 308th, 312th and 316th Divisions.

Day River Campaign

After Mao Khe, the war – and scenarios depicting it – escalate quickly. What follows then is a five-scenario long coverage of the Day River Campaign, where if playing vs computer you actually get to play both sides. First as Viet Minh, for the first two scenarios, it is important you’ll quickly learn the tactics to overwhelm the French positions. Using the cover of the night shall be important as well.

The Day River Campaign

Playing the French side, next, you will soon learn this war will actually take some serious effort if the French rule over Indochina is to be preserved. After the French counterattack, there’s two more Side B  first scenarios with Viet Minh with the initiative.

Day River campaign is also covered in scenario designer David Galster’s excellent de Lattre’s Line series: with the first blog covering the Day River Campaign itself. Recommended reading!

Hoa Binh – Operations Tulipe and Lotus

Having fought your hardest at Day River, the Hoa Binh Campaign and the two scenarios covering it await next:

Hoa Binh Campaign – Operations Tulipe and Lotus

There’s still some linear battling to be had before the Viet Minh learns to master the asymmetrical nature of the war in the latter years.

Operation Tulipe provides the French player with a nice chance to deploy some Hammer-and-Anvil tactics…

Operation Tulipe in Action

…while Operation Lotus and the road to  Kem Pass scenario will have them on the ropes trying to keep the few routes open against a clever and cunning enemy.

Road to Kem Pass, with a widescreen view – Can’t be that difficult, can it?

Both Hoa Binh scenarios have the French with the initiative, vs a stubborn Viet Minh element on the map.

Street Without Joy

Then, three more individual battles, first at Tu Vu where the Viet Minh is about to attack a French outpost, and Na San, a larger battle with the French player defending a hedgehog perimeter around Na San against a determined Viet Minh opponent.

Then, Street Without A Joy in a large, complexity 8 scenario by Jason Petho …

The Street Without Joy

,,, together with a huge map of the area, where under Operation Camargue, one the largest use of French forces set to clear the area:

Street Without Joy in its full glory (night graphics)

Definitively a chance for some misery and lack of joy, trying to find the evasive enemy before they vanish to the darkness of the night!

Operation Castor – Dien Bien Phu

From street without joy then to Operation Castor and Dien Bien Phu.

We all know how that will end, but hopefully there will be some joy to be had, with the scenarios available in the game? Dien Bien Phu is actually covered with a hugely excting ten-scenario series!

From parachuting to valley and  taking over the objectives there, towards a siege operation the medieval warlords would be jealous of. As the Viet Minh noose tightens, there’s less and less room to maneuver for the French troops. They won’t be sitting it out though, a good few French initiatives covered here as well:

Operation Castor – a happier time

With Dien Bien Phu series, you will again have a chance to play scenarios against computer both as the French or Viet Minh player. The French player is with the initiative with Bruno Arrives, Breakthrough to Isabelle, Bruno’s FlaK Raid, and the Battle of Five Hills, while the Viet Minh player has the first go with the rest, first assaulting the Beatrice strongpoint with scenario #2, and finally putting an end to it all with scenario #10, Castor Dies.

Worth a shout here are also the articles covering the famous battle by David Galster and available at, as part of Bruno’s Bunker series, for instance Operation Castor describing the French strategy behind Fortress Dien Bien Phu, and from the beginning of Bruno Arrives, to  the bitter end with Castor Dies.

KP 15

Also worth a shout – a lot of shouting going on here it seems – is the battle at the Kilometre Post 15, available here with yet another chance to have the French being ambushed by Viet Minh.

Kilometre Post 15

As per the scenario information above, tagged as ALL, the computer player shall be well equipped to handle either side here. ALL covers the head to head play against a friend as well, there will be plenty of Play by email or Hot Seat fun with all of these scenarios as well.

Missing a Battle?

Thanks for reading this far!

That’s twenty+ historical, thoroughly researched Indochina War battles covered in the game. Viet Minh, French formations, ARVN, and other troops such as the Catholic Militia, they all shall play a part.

Should that not be enough, should that one favorite historical skirmish miss from the set, worry not. While there’s over 100 scenarios included in Vietnam 1.0, there’s also the full set of editors available, per our usual standards. Complete with Orders of Battle for the era and a set of HUGE master maps to assist in creation of any new scenarios you’d like to see there.

Another set of blog posts is covering the new Campaign Series Event Engine to spiff those new creations even more up.

Next Stop: the Vietnamese Civil War

In the next blog post for this series we’ll be introducing the Vietnamese Civil War scenarios included in Vietnam 1.0.

Until then!

Campaign Series Event Engine in Vietnam 1.0: Triggering Events

Campaign Series Event Engine (CSEE) is a new system that allows scenario designers to script events in their scenarios to add more capabilities not seen before in the Campaign Series games. This system uses programmed Lua files to determine what the events are and how they interact with the scenario.

Triggering Events with CSEE

All of the scenarios that are included with Vietnam have a large component of the AI using the Campaign Series Event Engine where one side is fully scripted, providing an exciting opponent to play against. For the purposes of this Developer Diary series, I will look at what CSEE brings to Campaign Series from three viewpoints:

  • How Events are triggered in scenario Lua file
  • How Lua provides an easy to Adaptive AI settings, and
  • How the computer player with Scripted AI is a new kind of a foe.

In this post, I cover the first capability: how events are triggered and what you can do when that happens. Before that, a few words on the anatomy of CSEE itself.

Note: This is meant as an introductory blog about the coming features. There will be a complete CS Event Engine manual shipping out together with the game install. 

Campaign Series Modern Wars game engine vs. Campaign Series Event Engine

While there has been quite a few additions and enhancements built to Campaign Series game engine itself, none of them has been as exciting as the ability to react to anything happening in game – ie. having an event to taking place – in a scenario specific manner. And even though we combine the CS Lua Event engine with the game engine into one integrated game executable, on game launch, it is useful to think of the two engines as two separate programs running side by side. As an event takes place in the Campaign Series “Modern Wars engine” (built with MS Visual C++) it forks out a call to Campaign Series Event Engine “Lua engine”, running in parallel in the same process space. This is very efficient, too: you’d expect to see a little delay perhaps but no, it all plays together very smoothly.

Specifically, there’s a scenario specific Lua file available to catch these game event  calls, in any and all of the event functions now available. Once said event function has been processed in Lua engine, the control then returns to CS Modern Wars engine to continue with the game play there.

As with previous Campaign Series games, CS Vietnam 1948-1967 comes with a full set of editors. You can create your own scenario just like you did with previous games and their editors. Only now – it is an option – you can add a Lua programme file to the scenario you have designed. In that Lua file you can handle any game event in a manner that is relevant in the battle you are depicting.

Reacting to game events

Triggers available

Once an event takes place in the game, the game triggers an event function in the scenario specific lua code. Here are the event functions available at the time of writing this post. It is rather lengthy, but that’s the whole point, so here they are in all their glory:

  • on_air_attack (hc, pid, name, side, nation, points, strength)
  • on_arty_attack (hc, trackid, pid, name, side, nation, oid, orgname, points, strength, HQ, Leader)
  • on_build_barrier (hc, trackid, pid, name, side, nation, oid, orgname)
  • on_build_light_bridge (hc, dir, trackid, pid, name, side, nation, oid, orgname)
  • on_build_vehicle_bridge (hc, dir, trackid, pid, name, side, nation, oid, orgname)
  • on_clear_hex (hc)
  • on_clear_lz (hc, trackid, pid, name, side, nation, oid, orgname)
  • on_damage (hc, trackid, pid, name, side, nation, oid, orgname)
  • on_entrench_hex (hc, trackid, pid, name, side, nation, oid, orgname)
  • on_hex_assault (hc, side)
  • on_hex_attack (hc, side, nation, attype)
  • on_ied_attack (hc, trackid, pid, name, side, nation, oid, orgname, points, strength, HQ, Leader)
  • on_improve_hex (hc, trackid, pid, name, side, nation, oid, orgname)
  • on_lay_mine_field (hc, trackid, pid, name, side, nation, oid, orgname)
  • on_mine_attack (hc, trackid, pid, name, side, nation, oid, orgname, points, strength, HQ, Leader)
  • on_next_phase (turn, side)
  • on_next_turn (turn)
  • on_objective_capture (hc, values, side)
  • on_resume ()
  • on_set_ied (hc, trackid, pid, name, side, nation, oid, orgname)
  • on_shutdown ()
  • on_startup ()
  • on_unit_arty_fire (hc, trackid, pid, name, side, nation, oid, orgname, strength)
  • on_unit_attack (hc, trackid, pid, name, side, nation, oid, orgname, points, strength, HQ, Leader, attype)
  • on_unit_clockwise (hc, trackid, pid, name, side, nation, oid, orgname, points, strength, HQ, Leader)
  • on_unit_counterclockwise (hc, trackid, pid, name, side, nation, oid, orgname, points, strength, HQ, Leader)
  • on_unit_fire (hc, trackid, pid, name, side, nation, oid, orgname, strength)
  • on_unit_kill (hc, trackid, pid, name, side, nation, oid, orgname, points, strength, HQ, Leader)
  • on_unit_merge (hc, trackid0, pid0, name0, side0, nation0, oid0, orgname0, points0, strength0, HQ0, Leader0, trackid1, pid1, name1, side1, nation1, oid1, orgname1, points1, strength1, HQ1, Leader1)
  • on_unit_move (hc_from, hc_to, trackid)
  • on_unit_reduce (hc, trackid, pid, name, side, nation, oid, orgname, points, strength, HQ, Leader, loss)
  • on_unit_reinforce (hc, trackid, pid, name, side, nation, oid, orgname, points, strength, HQ, Leader)
  • on_unit_release (trackid, pid, name, side, nation, oid, orgname, points, strength, HQ, Leader)
  • on_unit_remove (hc, trackid, pid, name, side, nation, oid, orgname, points, strength, HQ, Leader)
  • on_unit_to_top (hc, trackid, pid, name, side, nation, oid, orgname, points, strength, HQ, Leader)
  • on_unit_to_bottom (hc, trackid, pid, name, side, nation, oid, orgname, points, strength, HQ, Leader)

Compare this to how it was with Campaign Series: Middle East 2.0 and you’ll find there’s approximately three times the events now as compared to CSEE’s first iteration back in the day!

On Objective Capture

Let us pick perhaps an obvious one: on_objective_capture (hc, values, side). Here’s how it looks in the scenario lua file:

On Objective Capture

So what happens is that each and every time an objective changes hands in the scenario played, there’s – in this particular implementation – a 2-in-3 chance the player would get an encouragement for his brave deed. See here:

Objective taken – commendations!

Also, note the parameters you receive in this particular event to have a look at:

  1. What were the hex co-ordinates of the objective (“hc”)
  2. What was the value, in Victory Points, of said objective (“value”)
  3. Which side captured said objective (“side”)

With that knowledge, what else could take place? Well, anything!

  • Loss of an important objective might lower everyone’s Morale by 1 step,
  • Certain reserves might receive an order to counter attack the objective viciously to win it back, or
  • This might actually trigger the Scripted AI to revert from battle plan “A” to plan “B”, what ever that plan then is.

On Unit Kill

Another example: on_unit_kill (hc, trackid, pid, name, side, nation, oid, orgname, points, strength, HQ, Leader)

A more complex example, yet nothing too complex right? With HQ units in Campaign Series representing bot the C3 (command, control, communications) capabilities as well as logistics (logistic chain as well as handling the rate of consumption), it might be prudent that a loss of any of your HQs triggers an penalty. It could be an Event Points penalty, as the standard code snippet suggests, or in this case, depending how important your HQ was there’s loss to logistics in that the base ammo levels go down. Supply does not flow to your troops as efficiently anymore!

HQ lost – logistics take a hit!

Stay tuned for more CSEE under the covers!

To summarise, with all those event functions available to be triggered, as that particular event takes place in the game play, sky’s the limit to enrich the playing experience.

In my next blog, then, I will talk about how to access the Adaptive AI parameters from CSEE Lua code. Here’s how it was available in its first iteration with Campaign Series: Middle East 2.0. Effective, but quite cumbersome. Now: way much easier, and, adaptive to game events to top it off!



Campaign Series Vietnam: General Update

As part of our usual transparency, we are letting you know of how the game will release.

Spooky turning the night into day with flares

In an effort to get the game to you sooner, we will be splitting up the game into the following:

  • Campaign Series Vietnam: 1948-1967 (which will include a little over 100 scenarios)
  • DLC #1 – Campaign Series Vietnam 1968-1979 (although the OOB’s will continue to 1985 and also include about 100 scenarios)
  • DLC #2 – Campaign Series Vietnam: Korean War (While this will focus on the Korean War, there will be some hypothetical fighting as well.
  • DLC #3 – Campaign Series Vietnam: Malayan Emergency 1948-1960

The primary reason for this is to get something for you to play sooner rather than later. I won’t offer a release date for the core game (although we’re aiming for the first half of 2021).

Why the delay? Well, we’re trying to build an exceptionally robust and realistic AI and this is a huge endeavor, especially when considering the complexity of the Vietnam War; the tactics, the strategy, the weapon systems and so on. Should we have started with East Front III for the AI? Probably, but alas, we didn’t.

That being said, the efforts we are doing on the AI is making this game like nothing you’ve seen or experienced before. As 97% of our users, based on our polls, will play again the AI at some point, we’ve focused all of our efforts to provide the best experience we can. On the bright side, once this core AI has been developed, additional games will be able to be released more regularly.

It is worth the wait and we appreciate your patience.

As an aside, while our focus is heavily on Vietnam, there is also work being done on East Front III.

Truong’s Tragic Trail #2: First Half Year 1973

Campaign Series Vietnam | Truong's Tragic Trail

Paratroopers, check your static lines!

Did you know that on paper, the South Vietnamese Forces vastly outnumbered the North. Yet, in 1973, the NVA began to gain advantages. This article explains how.

1973 Cease Fire

Henry Kissinger and Le Duc Tho signed the Paris Accords on 27 January 1973. Once this took place, the following military requirements were in force: All US forces withdraw, cease-fire in place with delineations of communist and government zones, withdrawal of foreign troops from Laos and Cambodia, ban on introduction of war materials in South Vietnam except for replacement, and a ban on further military personnel introduction into South Vietnam.

In addition, a Joint Military Commission  composed of the four parties, (US, SVN, DRV, PRG), and an “International Commission of Control and Supervision,” ICCS were established to police agreement terms. The ICCS was composed of Canada, Hungary, Indonesia, and Poland.

Project Enhance

Prior to the cease-fire, both sides sought to bring in additional equipment. The US had “Project Enhance,” which supplied equipment to the South Vietnamese armed forces, RVNAF. Table 1 lists equipment supplied in late 1972

Table 1.


Project Enhance was designed to raise RVNAF force structure to planned levels before the cease-fire.

Another effort, Project “Enhance Plus” augmented the South Vietnamese Air Force. (VNAF) Table 2 outlines aircraft provided.

Table 2.

Table 2.

The RVNAF planned for 1100000 personnel in fiscal year 1973.

Communists were also shoving great quantities of materiel, including field guns, tanks, and anti-aircraft weapons down the roads into South Vietnam, including SA-2 air defense missiles on their way to Khe Sanh in Quang Tri Province.

The Communists were not concerned about any imposed cease-fire restrictions on shipments to South Vietnam; the surge of shipments was instead in response to the heavy losses the NVA suffered during the 1072 Easter Offensive.

North Vietnam sent nearly 148000 replacements into South Vietnam during late 1972.

DAO (Defense Attache Office) Saigon was organized according to requirements established by the Joint Chiefs of Staff, CINCPAC, and MACV, and was activated on 28 January 1973 by Maj. Gen. John E. Murray. This became the US coordination function, and replaced MACV. The cease-fire agreement ended American advisory efforts. Senior DAO officials avoided any offer of operational advice to the Vietnamese, with whom they worked closely.

Balance of Power January 1973

The NVA had 15 Divisions in South Vietnam in January 1973, with approximately 148000 troops.

Supporting this force in COSVN and the Ho Chi Minh trail were about 71000. This totals 219000.

ARVN had an assigned strength of 450000. About 152000 were in 13 infantry divisions and another 10000 were in Ranger groups. The South Vietnamese Navy and Air Force had about 96000. The Regional Forces (RF) had 325000, Popular Forces 200000, and Women’s Armed Forces had 4000. The total is about 1.1 million.

The gross figures, 1.1 million for RVNAF vs 219000 NVA forces seem to favor South Vietnam, but a comparison of force structures and missions provide a somewhat better understanding. The 15 NVA divisions vs 13 ARVN does not take into account that the NVA had 27 separate infantry and sapper regiments, whereas the comparable ARVN units were only seven Ranger groups.

The missions were different. Communist forces were solely offensive, acting against fixed bases, villages, and communication lines. ARVN forces were mostly on the defensive. Thus, comparing 140 separate NVA battalions of infantry, sapper, reconnaissance, tank, and artillery to the 54 ARVN Ranger battalions and 300 or more regional force battalions is rather meaningless.

Considerations of NVA strength should also acknowledge the large administrative and logistical support force within North Vietnam similar to South Vietnamese backup forces. North Vietnam also did not have to defend lines of communication or base areas in North Vietnam from ground attack. It did have significant numbers to defend against air attack in North Vietnam, and to protect the Ho Chi Minh Trail through Laos and Cambodia.

Land Grab 1973

The NVA planned general attacks throughout most of South Vietnam immediately before the expected date of the cease-fire. These were known as “Landgrab 1973,” and occurred between 23 January and 3 February 1973.

In the northern areas, the NVA B5 Front did not launch anything but local attacks, because those forces were still rebuilding from the previous year. However, they did not give up any ground, and used heavy artillery to thwart ARVN attempts to advance along the coast toward Cua Viet.

Likewise, south and west of Quang Tri City, B5 Front forces prevented expansion of Airborne Division’s positions into the hills south of the Thach Han River.

The area around Hue was different. The Tri-Thien-Hue Front wanted to gain a political presence and get VC legitimacy. Elements of the 803d Regiment, 324B Division, moved into the lowlands south of Camp Evans, and regulars moved toward the lowlands north or Hue on 24 January. The next day, artillery and ground attacks began against RVNAF positions around Hue. Between 27 January and 3 February elements of the 803d attempted to interdict Highway QL-1 in the vicinity of the An Lo bridge.

Front-4 operations were conducted in Quang Nam, where 711th Division operated to contain the ARVN in the Que Son Valley, and prevented their advance to a logistical base in the Hiep Due region.   Front-4 completed attack preparations by 22 January 1973, including the 575th Rocket Artillery Battalion firing on Da Nang.

In Military Region 2 The NVA’s B3 Front included Kontum, Pleiku, Phu Bon, and Darlac Provinces, part of Quang Duc, and western districts of Binh Dinh. Objectives assigned to enemy forces in B3 Front were similar to those in southern MR 5: to hold the ARVN 23d Division in place, isolate the cities of Kontum, Pleiku, and Ban Me Thuot, and interdict the main highways. Attaining these objectives would effectively extend control over the population of the highlands.

In MR-3 north of Saigon, RVNAF intelligence indicated that Tay Ninh City might be attacked. But for reasons not fully clear, the Communists failed to allocate sufficient forces to capture the city. ARVN preemptive operations in January 1973 most likely eliminated the enemy’s capability to assign main forces to a Tay Ninh campaign.

The number and intensity of NVA attacks increased from 23 through 27 January against ARVN outposts, mostly on those defending major communication lines. Trang Bang, Trang Born, Highway 13 south of Chon Thanh, and Highway 15 south of Long Thanh were struck. NVA casualties were very heavy, however.

As ARVN preempted enemy operations in Military Region 3, it also did in the Mekong Delta. In an  operation known as “Dong Khoi.” the ARVN and territorials planned to attack for six days beginning on 15 January, but early successes were very good and the operation was extended six more days.

The Communists planned to capture areas with the greatest potential for subsequent exploitation and expansion. In the northern delta, they considered the border area with Cambodia from Ha Tien in the west to the Parrot’s Beak in the east to be most important. But, ARVN operation Dong Khoi thwarted these initiatives.


Consolidating and Rebuilding

The North Vietnamese developed a strategy consisting of two parallel elements: political and military. The political was the public element of the strategy. The North Vietnamese propagandized worldwide, and emphasized to the troops the following Landgrab related plan: Capture as much populated area as possible just before the cease-fire. Show the flag, and rely on the NVA main forces to contain the RVNAF while local forces entered villages. Wait for the arrival of ICCS teams declare and guarantee legitimacy of newly-won areas.


Directive No. 2/73, issued by COSVN coincided with the Paris Accord signing. This document announced the beginning of a new political struggle, in which military units were to play a secondary role in support of political efforts. The NVA was to help the VC to harrass the RVNAF, defend “liberated” areas, conduct terrorist campaigns, protect “mass movements,” and secure the resettlement areas.

One of the major components of the political offensive was propaganda. Their worldwide message was that Communists were scrupulously observing the cease-fire terms in the face of constant, aggressive violations by the other side. The only offensive operations undertaken by the Communist forces were to punish the “Thieu puppets” and promote peace.

While political efforts continued, unprecedented military preparations were underway in North Vietnam and along the Ho Chi Minh trail into South Vietnam. In order to deny observation of these preparations, the NVA deployed new anti-aircraft systems. The North Vietnamese were largely successful in denying VNAF visual or photo reconnaissance over sensitive areas, but were not so effective against US aerial photography.

In mid-March 1973 the NVA began a transportation effort that was to last almost to the end of the dry season. Convoys of unprecedented size, up to 300 trucks in each, headed south through Laos. Large quantities of food and ammunition were being received in storage areas in Quang Tri Province.

Heavy traffic was seen on Roule 534 from Laos to Hiep Duc in Quang Tin Province, and on roads into the B-3 Front area. Road improvements linked NVA units operating on coastal lowlands with Base Areas 609 and 702 in the Central Highlands. Similar route improvement activities were ongoing in Tay Ninh Province.

By September 1973, new pipeline construction was completed south of Da Long to a new storage site at A Luoi in the A Shau Valley.

The NVA took advantage of the American air interdiction halt of the Ho Chi Minh Trail to reinforce its tank and artillery strength in South Vietnam. Attrition during the 1972 Easter offensive had reduced the tank force to an estimated 100 vehicles. But, by the end of April 1973, estimated tank strength was close to 500.

NVA increased their artillery strength in South Vietnam by the introduction of 170 more 122- and 130-mm. guns, bringing the total to over 250. As was the case with replacement soldiers, no accounting was made to the ICCS, but ICCS teams nevertheless kept close track of US shipments into Bien Hoa, Da Nang, and other ports of entry.


First Half Year 1973

As the post-cease-fire flurry subsided, activities in the four military regions began to develop patterns that persisted through the summer of 1973. Each region was different.

In Military Region I, both sides avoided serious contact. The NVA continued consolidation and construction of major logistical bases in northern Quang Tri and western Thua Thien Province. The South Vietnamese used artillery sparingly, and little air power in defending outposts and coastal communication lines.

In Region 2, both sides developed strong positions around Kontum City. While the ARVN sought to keep NVA forces out or rocket range. While ARVN tried to keep Route 14 open south to Pleiku, the NVA’s 10th Division pressed against the city’s defenses to the north and west.

Another area of contention developed around the westernmost ARVN outposts of Plei Mrong and Plei Djereng. The latter was destined to fall because it was too close to Duc Co, the major NVA logistics base. The Communists also worked to improve their norlh-south logistical route from Dak To southward through the Plei Trap Valley.

The NVA 10th Division launched operations to control for the area north and west or Kontum City. The Montagnard hamlet of Polei Krong was attacked and taken by the NVA 95B Regiment. This was near ARVN defenses at Trung Nhia along the Poko River. With help from the 85th Ranger Border Derense Battalion at Paid Krong, ARVN held on to Trung Nghia with Regional Forces.

In Military Region 3 the NVA concentrated against Tong Le Chon, an isolated ARVN post deep in Communist-controlled northern Tay Ninh Province.  In March 1973, the NVA began a siege that lasted for a year. Although action elsewhere in the region was relatively light, harassment of outlying hamlets and resettlement areas continued.

In Military Region 4 the heaviest action centered in the Seven Mountains area of Chau Doc Province, where ARVN Rangers undertook a slow and costly campaign to destroy the remaining elements of the NVA’s 1st Division. Other intense combat occurred in the Hong Ngu region along the border  where the Mekong River enters South Vietnam.

General Ngo Quang Truong

Truong was an officer in the Army of the Republic of Vietnam, gaining his commission in 1954 and moving up the ranks in the Airborne Brigade. In 1966, he commanded 1st Division after helping to quell the Buddhist Uprising. He rebuilt the unit after this divisive period, and used it to repel the NVA, and reclaimed the imperial citadel of Hue after weeks of bitter street fighting during the Tet Offensive.

In 1970, Truong was given command of IV Corps in the Mekong Delta and improved the situation there such that some of his forces were redeployed elsewhere to resist Communist pressure. And, in 1972, he became commander of I Corps. He stabilized ARVN forces before turning back the Communists. In 1975, the NVA attacked again. This time, President Nguyen Van Thieu gave contradictory orders as to whether he should stand and fight or retreat and  consolidate. This demoralized I Corps, causing its collapse, and allowing the NVA to gather momentum, and overrun South Vietnam within two months. Truong fled South Vietnam during the fall of Saigon, and settled in Virginia in the United States.

Likewise, the numbers of anti-aircraft guns were greatly increased. Furthermore, they had SA·7 “Strella” Soviet hand-held, heat-seeking missiles. Also early in 1973, the 263rd SAM Regiment moved into Quang Tri Province, and set up near Khe Sanh. By the end of April, this regiment had constructed eight SA-2 sites around Khe Sanh and had placed weapons in four of them.

Campaign Series Vietnam | Truong's Tragic Trail

Truong’s Tragic Trail is the latest series of articles by David Galster that provides an overview of the events in Vietnam from 1973 until the end in 1975. The articles provide some interesting background information for the upcoming release of Campaign Series: Vietnam.

Truong’s Tragic Trail #1: Vietnam Endgame 1973-75

Campaign Series Vietnam | Truong's Tragic Trail

Paratroopers, check your static lines!

After the Paris Accords, the US no longer helped defend South Vietnam. This series of articles covers the period from Ceasefire to the fall of Saigon, 1973 – 75. The first provides an overview.

First Half Year 1973

Henry Kissinger and Le Duc Tho signed the Paris Accords on 27 January 1973. All US forces withdrew, and a cease-fire began. Introduction of war materials further military personnel were banned.

Prior to the cease-fire, both sides sought to bring in additional equipment. The US had “Project Enhance”, which supplied equipment to the South Vietnamese armed forces, RVNAF.

The NVA had 15 Divisions in South Vietnam in January 1973, with approximately 148000 troops, while ARVN had an assigned strength of 450000. About 152000 were in 13 infantry divisions and another 10000 were in Ranger groups. The missions were different. Communist forces were solely offensive, acting against fixed bases, villages, and communication lines. ARVN forces were mostly on the defensive. The comparison is rather meaningless.

The NVA planned general attacks throughout most of South Vietnam immediately before the expected date of the cease-fire. These were known as “Landgrab 1973”, and occurred between 23 January and 3 February 1973. The area around Hue was particularly affected as the Tri-Thien-Hue Front wanted to gain a political presence and get VC legitimacy.

The NVA strategy was similar in the four military regions: Hold ARVN in place, isolate the cities, and interdict the main highways. The North Vietnamese used the landgrab for propaganda. Capture as much populated area as possible just before the cease-fire. Show the flag, and rely on NVA main forces to contain ARVN while local forces entered villages. Declare legitimacy of newly-won areas to arriving ICCS teams.

North Vietnam began a transportation effort of unprecedented size, headed south through Laos. With this, the numbers of anti-aircraft guns and artillery were greatly increased.

In MR-2, both sides developed strong positions around Kontum City. In MR-3 the NVA concentrated against Tong Le Chon, an isolated ARVN post deep in northern Tay Ninh Province.  South Vietnamese conserved artillery and air power in defending outposts and communication lines.

The Military Balance MR I

“Cease Fire II”

On 13 June 1973 the four-party Joint Military Commission, (US, SVN, DRV, PRG), met in Paris and issued a communique calling to observe provisions of the 28 January cease-lire. This was followed by a decline in combat activity, reaching the lowest level since the “Landgrab.”

President Thieu felt the Communists were not likely to attack in strength during 1973, but would wait until the end of President Nixon’s term to launch offensives. He believed that President Nixon would intervene in such a situation.

Combat levels in Military Region 1 were relatively low, because the NVA’s northern Quang Tri and western bases and logistical routes were neither seriously threatened nor interfered with. At the close of 1973, the situation in MR-1 was such that ARVN regulars had control of major population centers and key lines of communication.

In MR-2 the situation was much hotter, as the NVA wanted to expand its hold on territory to control roads and logistics bases that approached Kontum. There were actions at Trung Nghia, and around Kontum. The NVA strove to extend its logistics corridor south along the western highlands, resulting in combat at Plei Djereng-Le Minh.

In MR-3 there were no major terrain losses for either side, but there were some areas of contact. The NVA exerted strong pressure against the Tay Ninh·Saigon corridor, with the most significant action along Highway LTL-1A between the Song Be River and Saigon. The NVA intentions  were to deny roads, isolate garrisons north of the bridge, and screen movement of artillery and supplies.

The Mekong Delta had been an annual contest for the rice harvest. Most Communist rice requirements, coming from South Vietnam, were obtained from the delta. The South Vietnamese strove to interdict communication lines to prevent rice shipment to NVA delta base areas as well as Cambodian collection points, where much of it was transferred to the other military regions.

One of three principal NVA infiltration routes, corridor 1-A crossed the Cambodian frontier near the border between Kien Phong and Kien Tuong Provinces, traversed the maze of canals through the Plain of Reeds, and ended in the watery wasteland called the Tri Phap.

The Military Assistance Service Funded program for Vietnam became obsolete with the departure of American forces in January 1973. The Congress, particularly the Senate, led by Senator Kennedy of the Armed Services wanted to reduce the amount of US aid. This led to shortages for important items such as ammunition, medical supplies, and purchase of more amphibious ships like LSTs.

The Military Balance MR II

Strategic Raids

The critical decisions in 1974 were made in Washington and Hanoi. The US Congress reduced assistance to South Vietnam, undermining their combat power and will to continue fighting. Hanoi was encouraged by the political fall of Richard Nixon. They foresaw 1975 as the year of victory.

Hanoi’s leaders knew of declining US support, and were emboldened. In early 1974, Hanoi’s military leaders studied the resolutions of the Lao Dong Party Central Committee’s 21st Plenum. The plam was to continue political and economic actions, and develop militarily for eventual victory. General Van Tien Dung described the situation:  “Our forces must grasp the concept of strategic offensive.”

NVA orders went to the various fronts, with training and maintenance preparations in the North, and  offensive operations in the South. Only in the Mekong delta, and Svay Rieng Province did the RVNAF emerge victorious.

Svay Rieng and sizable NVA forces was a serious threat to their adjacent provinces. A two-pronged attack by ARVN 10th Infantry Regiment was to clear the southern edge of Tri Phap. NVA casualties were heavy, and ARVN captured tons of ammunition.

Svay Rieng has two minor prominences, Elephant’s Foot and Angel’s Wing. The NVA 5th Division assembled forces in Svay Rieng. Lt. Gen. Pham Quoc Thuan, III Corps Commander, decided to reduce the threat to his western flank. Three armored task torces drove west from Go Dau Ha, sweeping through Cambodian NVA bases. The threat to the vital road junction at Go Dau Ha was substantially reduced. ARVN was in complete control of the battlefield.

In spite of ARVN successes at Tri Phap and  Svay Rieng,  the North Vietnamese pressed ahead with their “strategic raids” campaign against the crucial defensive perimeter north of Saigon. The first to fall was unimportant outpost of Chi Linh. Ultimately, the NVA would attack a dozen locations in MR-3.

The NVA 141st Regiment overran the Chi Linh base. Tong Le Chon had been under siege since the cease-fire, and finally ARVN 92nd Ranger Battalion had to abandon it.

Two 7th Division NVA regiments attacked at Phu Giao, but ARVN 5th Division and the 318th Task Force thwarted this effort.

The 9th NVA Division pressed into the Iron Triangle taking Ben Cat and Rach Bap, and pushing deeper toward Saigon. But the ARVN 18th Division eventually recovered all lost ground in a several month campaign. This may have caused a major ARVN command shakeup in October.

As NVA forces conducted strategic raids north of Saigon, forces of the B·3 Front and the NVA Military Region 5 embarked on a campaign to eliminate isolaled ARVN outposts in the Central Highlands, and move into the coastal lowlands of MR-1 and 2. A successful NVA thrust was at Chuong Nghia east toward Quang Ngai.

The NVA strategic raids campaign accomplished three things that placed their forces in an excellent position for a major offensive. 1) Despite high losses, they severely depleted ARVN forces of experienced leaders and soldiers. 2) COSVN command, staff, logistics, and communications had been greatly expanded. 3) NVA gained ground on the edge of the coastal plain, and were within artillery range of major South Vietnamese installations and population centers.

The Military Balance MR III

The Tightening Noose

In early 1974, the NVA maintained pressure on ARVN defenses south of Hue. These skirmishes eroded the ARVN 1st Division, which protected the Phu Bai Airbase, coastal Route 1, and the Ta Trach River corridor.

The NVA infiltrated the Hai Van Ridge in October 1973, but ARVN still held on the defensive ring protecting Phu Bai and Hue. After a new II Corps HQ was formed, the NVA 324B Division now controlled five regiments that attacked th hills south of Phu Bai.

Heavy fighting continued into September, with strong NVA attacks and Bloody skirmishing against the ARVN 1st Division elements.

By making timely and appropriate deployments, General Truong was able to hold the NVA forces at bay around Hue. But, the ring was closing on the Imperial City.

The 1974 NVA campaigns were stalemated at Thua Thien and around Saigon, but had overrun isolated bases in the Central Highlands, and penetrated the Quang Nam lowlands. In the highlands, NVA forces captured Thuong Duc, a district capital, and protracted paratrooper division counterattacks were repulsed. This victory and numerous others showed the North Vietnamese high command that it was time for a bolder strategy.

General Van Tien Dung related how the “General Staff reported to the Central Military Party Committee that the combat capability of our mobile main force troops was now altogether superior to that of the enemy’s, and the war had reached its final stage, and the balance of forces had changed in our favor.” Phuoc Long would be the first test of this assessment.

Phuoc Long Province’s capital was Phuoc Binh on the Song Be River. The 301st NVA Corps ran  the Phuoc Long campaign using the 3rd and 7th Divisions, a tank battalion, an artillery and anti-aircraft regiment, and several sapper units. This formidable force concentrated against four dispersed RF battalions and PF platoons. One by one,  isolated garrisons came under attack and were overrun.

ARVN defended Phuoc Binh with a couple RF battalions and eventually the 7th Infantry Regiment and the 81st Airborne Rangers. But as NVA tanks rolled through the streets, and fired at ARVN positions, NVA sappers followed, mopping up bypassed positions. NVA artillery was devastating, as structures, bunkers, and trenches collapsed, and casualties mounted.

The NVA had captured the first province capital since the 1973 cease-fire. ARVN losses were staggering. The few province, village, and hamlet officials captured were summarily executed.

As expressed by one Vietnamese driver, ” . . .even the gods were weeping for Phuoc Long.”

The conquest of Phuoc Long Province was clearly the most blatant breach of the cease-fire agreement thus far. On 13 January, the US State Department released an official protest.

However, President Ford made no mention of Vietnam in his State of the Union message on 15 January. In a later press conference, he said that he could foresee no circumstances in which the US would re-enter the Vietnam War.

The dramatic Phuoc Long victory, vs the passive US response, confirmed earlier North Vietnamese estimates that the time for a major offensive was at hand. Plans for the spring offensive were made in a conference in Hanoi.

The Military Balance MR IV

Fall of Saigon

General Dung reported on 9 January, one day after the Poltical Bureau’s conference adjourned, the Central Mililary Party Committee met to prepare military plans. It was here that Ban Me Thuot was selected as the first objective, and main effort of the Central Highlands campaign.

Central Highlands

The B-3 Front counted on surprise and overwhelming force to capture Ban Me Thuot, with diversionary attacks in Kontum and Pleiku Provinces to prolong these advantages, and prevent  ARVN reinforcing. Diversions began, while the 10th, 316th, and 320th NVA Divisions converged on the initial objectives.

While these events deceived General Phu into thinking Pleiku was the main NVA goal, Communists interdicted Route QL-21, by blowing two bridges and overrunning an outpost between the Darlac boundary and Khanh Duong, thus isolating the Central Highlands battlefield.

Rocket and artillery fire fell on Ban Me Thuot on 10 March, and by midmorning, 320th NVA Division elements penetrated the city. Already, ARVN  General Tat was ordered to evacuate Kontum and Pleiku, down Route 7B to the coast at Tuy Hoa. The evacuation of all South Vietnamese forces from the highland provinces had begun on 19 March.

Final Offensive in the North

On 8 March, the NVA attacked in three northern provinces of MR-1, Quang Tri, Thua Thien, and Quang Nam. General Truong, I Corps commander wasordered to send the Airborne Division to Saigon. A collapse was imminent in Quang Tin and Quang Ngai Provinces, while shifting units in Quang Tri continued.

On March 18, Truong was directed to defend Hue, Da Nang, Chu Lai, and Quang Ngai City. When forced, he could surrender Chu Lai and Quang Ngai. But, he must defend Hue and Da Nang at all costs. The Marine Division, defending Da Nang was ordered to Saigon.

The defense of Hue was a confusing command and communication blunder. At first Thruong was told to withdraw, then later to defend Hue at all costs. But, the citizens there began fleeing once it was being hit by NVA artillery, and its defenses withdrew

The situation in Da Nang on 26 March was chaotic, but 3rd ARVN Division still held in Dai Lac and Duc Duc districts  against mounting pressure. NVA rockets struck a refugee camp near Da Nang.

Soon it was evident that 3rd Division could not contain NVA attacks in Quang Nam.

Attempts to hold that line failed as ARVN soldiers deserted to save their families. With defeat imminent, General Truong shipped all forces, mostly marines, to Saigon.

Last act in the South

The 1975 coordinated Communist offensive struck first at Tri Tam, and in its possession, the NVA now controlled the Saigon River corridor from Tong Le Chon, to the ARVN outpost at Rach Bap.

While General Toan committed a half-corps to the west, an NVA offensive erupted in the east and center. Available ARVN forces were inadequate to cope with the attacks. Enclaves at An Loc and Chon Thanh were of no further military or political value, and ARVN forces were withdrawn.

Just before the NVA attacked, 18th ARVN Division was spread in several areas: Xuan Loc,  Dinh Quan, Hoai Duc, and Bien Hoa. that two NVA divisions, the 6th and 7th, were committed in Long Khanh and the main combat was at Xuan Loc.

South Vietnamese fought well at Xuan Loc, but the NVA used the battle as a “meat grinder”, sacrificing its units to destroy irreplaceable ARVN forces. Meanwhile, I Corps could slip to the west and prepare for an assault on Saigon.

The NVA continued sending additional forces into Military Region 3. I Corps set up its headquarters in Phuoc Long, but sent the 320B and 325th to Long Khanh, to join  the fight at Xuan Loc.

JGS and ARVN III Corps augmented Saigon defenses battles continued elswhere. General Sa, commanding the 25th ARVN Division, and deployed it at key strongpoints around the the city. Three Ranger Groups were set up west of Saigon, and the inner city would be defended by territorials, and a few regular formations.

Far to the northeast of the capital, battles for Ninh Thuan and Binh Thuan Provinces were fought. 3rd NVA Division attacked on 14 April against 2d ARVN Division. These were initially repulsed, but defenders were overwhelmed on 16 April, and Phan Rang was lost.

Hope that the North Vietnamese might stop the offensive and negotiate, President Thieu resigned office on 21 April. But, removal of this long-trumpeted obstacle to reconciliation had no discemable effect.

The NVA resumed attacks on 26 April, with focus on Bien Hoa, east of Saigon. After heavy artillery fire, the NVA began moving toward Bien Hoa. Route 15 was interdicted, isolating Vung Tau, and Da Ria fell.

On 29 April, heavy bombardment of Tan Son Nhut airfield began. Cu Chi was under attack, and NVA sappers and infantry were in Go Vap, just north of Tan Son Nhut. By 30 April, the American evacuation was complete. That morning, Duong Van Minh surrendered the country to the North Vietnamese Army.


“Vietnam from Cease-Fire to Capitulation”, Col. William E. Le Gro, CMH Publication 90-29

” Our Great Spring Victory”, General Van Tien Dung

Campaign Series Vietnam | Truong's Tragic Trail