Nguyen Van Thieu, who served a decade as South Vietnam's wartime president and fled into exile just days before his country fell to Hanoi's communist troops in 1975, died on September 29th aged 78, having long clung to the belief that he was betrayed by his US allies in the final months of the war.
Nguyen Van Thieu's death leaves many questions unanswered. Among them: Why did he abandon South Vietnam's highlands to Hanoi's invading troops in March 1975? That decision led to the fall of Saigon a month later, bequeathing him a controversial legacy and turning him, during most of his exile in Taiwan, Britain and the US, into a virtual recluse.
He was a trim, pipe-smoking man who stood 5ft 6ins and started every morning with rigorous calisthenics.
He played a pivotal role in virtually every major Vietnam event for a decade, from the overthrow of the Ngo Dinh Diem government in 1963, to the 1973 Paris peace accords, which he bitterly opposed, to the final, chaotic days before Saigon's fall. He had already fled when North Vietnamese tanks crashed through the gates of the presidential palace on April 30th, 1975, to end a war that cost the lives of three million Vietnamese and 58,000 Americans.
But his secrets go with him to the grave. He never wrote a memoir, granted no more than a handful of interviews and received few visitors. Neighbours saw him from time to time walking his dog but knew little about him or his post-war life.
Nguyen Van Thieu was born on April 5th, 1923, the youngest of five children, in the dirt-poor town of Phan Rang in central Ninh Thuan province. His father, a fisherman-farmer and small landholder, was relatively prosperous by local standards.
Along with the help of his brother, Nguyen Van Hieu, a top government official, he attended the Merchant Marine Academy and the National Military Academy in Dalat. He was commissioned a second lieutenant in 1949, and as an infantry platoon commander in the campaign against the Viet Minh (later known as the Viet Cong) he became known as a good strategist and a capable leader.
In 1954, as a battalion commander with the rank of major, he led an attack on the Viet Minh, forcing the guerrillas to withdraw from his home village of Phan Rang - and his family home, which they had occupied.
He went on to become a division and corps commander and twice, in 1957 and 1960, was sent to the US for further military training.
In November 1963, he directed an attack on the barracks of Diem's presidential guard, helping ensure the overthrow of the military regime and Diem's assassination.
As a reward, he was made secretary-general of the Military Revolutionary Council that held power in South Vietnam.
South Vietnam had 10 governments in the 19 months after Diem's death. The US, desperate for an anti-communist leader to unify the splintered segments of society, put its considerable influence behind Nguyen Van Thieu, a Buddhist who converted to Catholicism and a man who belonged to no military or political clique.
With US backing, he was elected president in October 1967. He promised democracy and social reform and that he would "open wide the door of peace and leave it open". He was re-elected in 1971; both elections were widely seen as rigged.
His governments were rife with corruption, greed, incompetence and petty political jealousies. But Washington stuck by him as the best man to carry on the war, and he proved to be an obedient and loyal ally.
He supported President Johnson's decision in March 1968 to curtail the bombing of North Vietnam in order to start peace talks. But he always believed - and was proved correct - that Hanoi's goal was total victory, not a negotiated settlement.
Only under relentless pressure from Washington did he agree to sign the Paris peace agreement in January 1973, which led to the withdrawal of US combat forces but allowed Hanoi to keep its troops in place in the South. He said President Nixon had promised that the US would respond forcefully to any North Vietnamese attempts to grab the South's territory.
But a year later, President Ford did nothing when Hanoi launched a major attack on Binh Long province. To both Hanoi and Nguyen Van Thieu, the signal was clear: The US had had enough of the war.
"The Americans promised us - we trusted them," he said later. He resigned on April 21st 1975.
Five days later, he was gone, headed for Taiwan in a US C-118 transport plane, carrying 15 tons of luggage and - according to many reports, which he always denied - $15 million in gold.
Nguyen Van Thieu: born 1923; died, September 2001