1950 French Manuscript Military Map, First Indochina War

A c. 1951 diazotype map with significant manuscript annotations produced during the First Indochina War between French forces and the Viet Minh independence movement. It depicts a portion of the Lower Red River Valley in Tonkin and provides detailed information on French forces during their struggle against the Viet Minh, most likely during the Battle of the Day River.

A Closer Look

Coverage includes the lowest portion of the Red River Delta and the southernmost part of Tonkin, concurrent with Nam Định and Ninh Bình provinces. The Red River, running northwest-southeast across the map, along with its tributaries, other waterways, roads, and the Pacific coastline are illustrated. Cities and towns are indicated throughout, with red, green, blue, yellow, or multicolored circles, perhaps marking the nature of the forces garrisoned there (French Expeditionary, Foreign Legion, Vietnamese National Army, local militias, etc.). Near each circle is the name of the settlement and a series of letters and numbers which presumably indicate the units and numbers of French and French-aligned troops present there. Several settlements are crossed out with large Xs, suggesting that they had been either abandoned or 'cleared'.

At Yen Phu, the word 'déminage' appears in parentheses, referring to mine clearing. The use of landmines was limited in the conflict compared to Second Indochina War (1955 - 1975), but they were used and caused casualties, including Ishii Takuo (石井卓雄), a Japanese officer who stayed in Vietnam after the surrender of Japan to train Viet Minh fighters. He was killed in May 1950 and afterwards enshrined in the Yasukuni Shrine in Tokyo.

Battle of the Day River

The immediate context of this map is very likely the Battle of the Day River (Bataille du Day / Chiến dịch Hà Nam Ninh), which took place between May 30 and June 18, 1951, around the Day River, a distributary of the Red River. In the preceding months, the French had fortified this portion of the Red River Delta, which was a relative stronghold for them as the heavily Catholic population of the region had little interest in the anti-clericalism and Marxism streak prominent within the Viet Minh. The Viet Minh commander, Võ Nguyên Giáp, sought to use newly trained and equipped forces to launch a full-scale offensive against the French, transitioning from earlier tactics that were defensive in nature or quick hit-and-run attacks. Through March and April, Viet Minh forces launched guerilla attacks around Ninh Binh and other cities in the region to prepare for the offensive. But in late May, the French organized counterattacks to disrupt the ability of the Viet Minh to control the countryside, setting off a full-scale battle. The French commander, Jean de Lattre de Tassigny, whose son was killed at the start of the battle, matched the fluidity of the guerillas, effectively working to methodically cut their supply lines, and forcing them to withdraw from the region with heavy casualties by mid-June.

First Indochina War (1946 - 1954)

The First Indochina War was a continuation and intensification of the Vietnamese independence movement, which was aided by the upheavals of the World War II (1939 - 1945). Events in China played an important role in laying the groundwork for the struggle. Vietnamese independence activists were strongly influenced by Chinese intellectual currents (nationalism, anti-imperialism, agrarian Marxism) and the 1937 Japanese invasion of China pulled Vietnam into a wider regional conflict. As France was neutral in the Sino-Japanese conflict, and unable to police the border between its Indochinese colonies and China, Tonkin in particular became a conduit for supplies to the wartime base of the Chinese Nationalists at Chongqing.

As France fell to Hitler's armies, the Japanese Empire moved to occupy Tonkin to cut off supplies to Chongqing. The French colonial administration was left in place in Vietnam, but Japan had final say on the most important matters. Japan's occupation weakened the power and prestige of France and allowed independence activists, including Ho Chi Minh, to return from exile and organize (in 1941, Ho co-founded the Viet Minh). The war years also led to brutal shortages, including a famine in 1945 that killed as many as 2 million people.

The sudden end of the war in August 1945 led to a power vacuum. Occupying Allied troops took weeks to arrive, and when they did, they were Chinese or British instead of French, as France itself was still recovering from German occupation. In the interim, Ho Chi Minh declared the independence of Vietnam in Hanoi on September 2, 1945. Though French troops did eventually reoccupy Hanoi, with Ho's reluctant assent on the promise that Vietnam would become a 'free state' within the French Union, both the departing Japanese troops and occupying Chinese forces were sympathetic to the revolutionaries' struggle and provided them with aid. Around this time, the broad alliance of Vietnamese anti-imperialists began to break down, and the disorganized Chinese-backed Vietnamese Nationalist Party lost influence to Ho's leftist movement within the Viet Minh.

The uneasy peace between the French and Viet Minh broke down in November 1946 following the Haiphong incident, when a French cruiser fired indiscriminately into civilian areas of Haiphong following a skirmish, killing several thousand. French garrisons were well-ensconced in Hanoi and Haiphong and backed by naval gunships, but Ho and his leading general Võ Nguyên Giáp pursued a guerilla strategy. The French launched a series of counter-insurgency offensives that inflicted heavy losses on Viet Minh forces, while also granting greater levels of autonomy to a friendly indigenous government led by Bảo Đại, the last Nguyen emperor.

But a major boost to Viet Minh forces came in late 1949, when Chinese Communist forces occupied southern China. This provided a steady supply of weapons, supplies, and advisors to Viet Minh forces across the border in Tonkin. New units capable of launching full-scale offensives were formed, armed, and trained. The tide began to turn perceptibly towards the Viet Minh. In December 1950, a new French commander, Jean de Lattre de Tassigny, was appointed, and he quickly moved to solidify defensive positions in the Red River Valley (known as the 'de Lattre line'). At this point, the war settled into a stalemate, as the Viet Minh had numerical superiority and an advantage in morale, but the French maintained air superiority and could bring naval power into play near the coast.

Viet Minh troops became increasingly effective at guerilla tactics, wearing down French supply lines and morale. The French responded by creating fortified 'hedgehog' outposts, launching airborne raids deep in Viet Minh territory, and using napalm to expose and disrupt Viet Minh supplies and bases, even while their own commanders privately acknowledged that the war was unwinnable (all presaging the tactics and struggles of the Americans in southern Vietnam). The breaking point came with the Battle of Dien Bien Phu in March - May 1954, when the French overcommitted to a distant 'hedgehog' outpost that was difficult to relieve or resupply, leading eventually to the garrison's surrender. Afterwards, the French government fell, and the 1954 Geneva Accords were signed, allowing for the independence of North Vietnam.

Diazo Print or Whiteprint

The diazo print (whiteprint or diazo for short) is a photo reproductive technique best understood as a reverse cyanotype or blueprint. The process yields distinctive blue lines on white paper. Like cyanotypes, the diazo process gained popularity in architecture circles, where it was a simple and effective way to duplicate documents in the field. The earliest diazotypes appeared around 1880 and were adopted for military and field cartographic use from about 1895. The diazo process was commercialized in 1923, when the German firm, Kalle and Company, developed Ozalid, a patented diazo paper that made diazotyping even easier. By the 1950s, it supplemented cyanotypes as the reprographic technique of choice for technical drawings.

Publication History and Census

This map was very likely produced by French military forces in Tonkin in 1950 or soon afterwards. As a diazo print, it was meant to be used on site, and the extensive manuscript annotations indicate that it was. This is a unique item and an incredible survival from the battlefield some 70 years ago.