The man had come in to buy soy sauce. Tran Thi Ngai was working as a midwife and nurse, but that morning she was looking after her parents’ shop in southern Vietnam while they were out.

He had grenades hanging from his armour, guns on his belt. It was the summer of 1967, and the Vietnam War - pitting South Vietnamese forces, the US and its allies, against the North Vietnamese Communists - was escalating.

As he approached the counter, he held out the money. As Tran reached to take it, he grabbed her arm, then her hair, and dragged her into the back room of the shop. There he raped her.

“It felt as if my life was over,” Tran says. All she could do was channel her energies into working harder than ever.

When she noticed her stomach swelling she assumed she was just putting on weight. Then one day she felt a kick and realised she was pregnant.

Her parents were horrified that she was expecting a baby out of wedlock - a major taboo. The country’s social mores were heavily influenced by Confucianism, and women were expected to remain virgins until they were married.

“My parents called me ‘chửa hoang' (pregnant out of wedlock) - they beat me up badly.

“I didn’t want to carry on living. I felt completely dead inside.”

She tried to kill herself several times but survived - “it felt as if the foetus was fighting for me”.

Her parents only stopped beating her once she gave birth - in February 1968. She was overwhelmed by how beautiful her baby girl was, but was soon overtaken by anxiety.

“I was worried about my child growing up, worried about money, worried about how I could get back to work to earn a living.”

She named the baby Oanh. But, hard as it is to comprehend, she wanted to recognise the baby’s father in some way. The middle name would be Kim. That was the soldier’s surname. Her rapist was neither Vietnamese nor American. He was South Korean.

Four years earlier his nation had joined the US in fighting the Communist Vietcong in South Vietnam.

Not long after giving birth, Tran woke one night to find that Kim had appeared again, looking for her.

“He didn’t say a word, stood there for one or two minutes, then left,” she says.