If it hadn’t been for his father, Craig Holmes might never have returned the graduation ring given to him 30 years earlier by a teenage girl he helped rescue from the South China Sea. Holmes was training to be a navigator on board a British ship hauling a cargo of millet to Taiwan in the autumn of 1978. Off the Vietnamese coast, the hulking steel vessel crossed paths with a small, crowded and leaking wooden fishing boat holding Luisa Van Nu and 345 other people fleeing the communist takeover of their country.

The refugees were into their fourth day at sea and hope for a new life had given way to despair as it seemed inevitable the boat would sink. Mothers pulled their children close. Fathers spilled regrets at taking their families to their deaths. Then the MV Wellpark, run by a Scottish shipping company, appeared out of the storm. The difficult and dramatic rescue earned its captain, Hector Connell, an MBE. But that recognition came only after the destitute refugees found themselves caught up in an international political wrangle over who would take them in. In the end, the then Labour government agreed to bring them to London despite the alarmist cries of Britain “being full” and warnings that it would open the door to floods of refugees.

Holmes gave up his cabin for Van Nu’s family. As she left the ship for London and a country she knew nothing about, the 19-year-old seaman handed her a keepsake. “I had a necklace I’d bought in Peru,” Holmes recalled. “It was silver. A nautical wheel with a crucifix in the middle. I gave that to her and said: ‘Remember us from the Wellpark.’ She took off one of those pinky rings, her high school graduation ring, and gave it to me.”

I heard someone say: ‘This is it. The water’s coming in and the boat will go down'

Holmes said he viewed the rescue as little more than a bit of adventure to break up a long sea voyage and it quickly slipped into history. He went on to captain his own ships before settling as a maritime pilot in New Zealand. “My dad had the ring for a while because, being older perhaps, he realised more what we’d done than I did, really. He used to wear it around his neck on a chain. If he hadn’t kept it, it might just have got lost, showing how vacuous I was at the time. When he died I got it back again and it sort of meant a bit more then.”

Holmes stuck the ring in his wife’s jewellery box where it sat until word reached him that the Vietnamese rescued by the Wellpark were planning a 30th-anniversary reunion in California, where some had settled.

Safe haven: the rescued people look through donated clothing on the deck of the Wellpark. Photograph: Mike Newton

“When I went to the reunion, I thought I’ll take it and give it back to Luisa. She was quite emotional about getting it back after all those years,” he said. “To me the rescue was just a night of adventure. What we’d actually done didn’t come home to me until I went to the reunion. There were a couple of boys, about four or five, and I suddenly thought: ‘Fuck me, this is another generation.’ These kids wouldn’t be here if their mum hadn’t been dragged on board the Wellpark. I realised then that what was a night of adventure for me was life or death to them.”

In October 1978, 346 people crammed into the three decks of the 60ft fishing boat to join one of the great migrations by sea of modern times. Around 800,000 boat people, as they became widely known, are believed to have fled Vietnam by sea. Many others drowned or were captured, raped and killed by pirates, particularly from Thailand.

As the boat entered the Mekong Delta it damaged its rudder and lost its steering. The refugees headed out to sea with no idea where they were going. Among them was nine-year old Diep Quan, whose family had two strikes against it when South Vietnam fell to the communists because her father was a businessman and her parents were of Chinese ethnicity. On the day they left, her mother announced a family holiday. “My uncle came round with a truck because he was a goods driver. I was a city girl and all I remember is trees, jungle, mud. What’s this about? This is a weird place for a holiday,” she said. Then she saw the fishing boat moored on the Mekong River and understood she might never see Vietnam again.

My father gave me a tube of toothpaste. Inside was a $100 bill. He said: ‘I’ll see you later.'

Sitting in a London coffee shop, swinging between tears and laughter as she recalled a journey and a life that was very nearly cut short, Quan described the first day at sea as “a paradise” of infinite ocean and flying fish. Then the boat hit the wake of Typhoon Lola and started to fill with water. A chain of young men bailed out with buckets, but they could only delay the inevitable.

The refugees spotted ships and fired flares, but either they were not seen or the crews ignored them. The captain told his passengers the boat could not struggle on much longer. “I heard someone say: ‘This is it now, the water’s coming in and the boat will go down,’” said Quan. “My dad had been up on deck. He decided, if this is it then he’s going to come and sit with his family. All the menfolk came and sat with their families.”

Quan wiped away a tear as she recounted, years later, asking her mother if her father ever regretted the decision to get on the boat. “She said, ‘Of course he did.’ When everyone had said, ‘Right that’s it, we’re going to sink,’ he was talking to my uncle and they were saying: ‘We really shouldn’t have done this. We’ve taken everyone to their deaths,’” she said.

‘I’m one of Thatcher’s children’: Diep Quan, now an IT trainer, at Morgan Stanley in Canary Wharf, London. Photograph: Suki Dhanda/The Observer

Two brothers, Hung and Huy Nguyen, were on board with their other siblings and parents, who owned a cinema chain in Saigon before it was seized by the new communist government. Hung was 18 and chose to leave even though he had won a prized place at medical school. “There was no question about whether I should go or not. As a medical student you are cream of the crop, but you’re also government property,” he said. “Growing up at that time, it really bothered me because of the freedom thing. They can stop you on the street and cut your hair if your hair is too long. When you talk, you have to watch your mouth.”

As the passengers grew more fearful, Hung’s mother called for him and 15-year-old Huy to sit with her. “She called all the kids over so she could see us. We didn’t really understand, but now we know,” said Huy.

One of their uncles, who Huy thinks may have been autistic, leapt over the side into the sea, saying he was going to swim back to Vietnam. Acceptance of what seemed like the inevitable was broken by someone shouting that they had spotted a ship. The captain fired a flare. It was seen by an officer on the Wellpark’s bridge.

Someone tried to bring a bag on board. I said, ‘No baggage.’ They opened it and there was a kid inside

“We thought it was a battleship,” said Huy. “In the night, it was lit up with all these cranes which looked like cannons.” Captain Connell sent a lifeboat to investigate. Waiting anxiously on the fishing boat deck was Stephen Ngo, just 13 years old and the only child travelling on his own. Ngo had gone down to the boat to see off his older brothers, but his father sent him off instead at the last minute. “He gave me a tube of toothpaste. Inside that toothpaste was a $100 bill. He said: ‘Take this with you and I’ll see you later.’” Ngo would not see his father for years.

The crew of the lifeboat struggled for hours, rowing through the heavy swell to make two trips picking up a few dozen refugees. Captain Connell decided to bring the ship alongside the fishing boat and take the refugees off directly. It was a remarkable act of seamanship.

“I was leaning over the side with a heaving line,” said Holmes. “Someone tied it to a bag. I shouted down: ‘No. No baggage. We’ll get baggage later.’ A guy on the boat opened the bag and there was a kid inside it.” That was the end of the no-baggage policy. “I lifted this kid up and that was the start of what turned out to be a good way to get the kids on board. Any kids that would fit into this red Adidas bag. I lost count of how many I brought up in that.”

At just four, Paul Tran was too small to climb. He was pulled up in a net. “My head banged on the ship as I was hauled up. Woke me up,” he said.

‘For us, the crew were heroes’: Diep Quan, middle row far right, with her sister. They are pictured on the Wellpark after being rescued. Photograph: Mike Newton

Most of the refugees were packed on to the decks in a makeshift village under tarpaulins strung over the hatch covers. “They just looked like poverty-stricken vagrants, really,” said Holmes. “Some of the kids were just in vests and nothing on the bottom at all.”

The Wellpark sailed on to Taiwan, where the government was sympathetic, sending food and clothes to the ship, but insisted they would not be allowed to leave the ship until the UK agreed to take them in. After two weeks of pictures of the destitute refugees on the news, the British government said it would bring them to London. “This is when we realised who we had on board,” said Holmes. “Doctors and nurses. A couple of lawyers. We had a whole typing pool. There were typewriters banging away, doing all the paperwork.”

The refugees were not universally pleased at being told they were going to Britain. Some were keener on the US, a country they knew more about. “Back in Vietnam we had a very bad impression about the British,” said Huy Nguyen. “We thought the British were very snobby. That they wore top hats and used their gloves to slap people’s faces.”

The 346 were flown to Stansted airport and taken by coach to Kensington army barracks. “We arrived in the middle of the night,” said Huy. “It was foggy and it was cold and it was really depressing. But when we got to the barracks people were waiting for us, to give us soup. They put flowers on our beds. Roses or coronations. I got a carnation. White. I was really happy.”

Gifts poured into the barracks. A circus visited, complete with an elephant for rides. Woolworths laid on a Christmas party for the children. The reception in the press was generally welcoming, even among tabloids as hostile to immigration then as they are now, perhaps because the Vietnamese were fleeing communism. The Daily Mail wrote: “Because we have closed the door to mass immigration – and rightly so – it does not mean we need be deaf to the knocking of some of those whose claim to help requires no passport or birth certificate to establish its piteous authenticity.”

But official hostility was rising. Within a few months Margaret Thatcher was prime minister, confronted with four more British ships rescuing hundreds of boat people. She was strongly against taking them in, ostensibly on the grounds of being “fearful of UK public opinion”, even though the UK had accepted only a tiny fraction compared to the 250,000 Vietnamese refugees admitted by the US and 60,000 by France. A Home Office memo warned that accepting more “would be seen as leading to an influx of immigrants which we could not control”. Thatcher eventually relented over the ships already carrying boat people, but demanded “a cast-iron position in legal and political terms which would enable the UK to hold out against admitting refugees”. She also wanted Britain to withdraw from the 1951 refugee convention.

All of this went largely unnoticed by those rescued by the Wellpark as they sought to map out a future in a strange land. Quan’s father applied to emigrate to the US, but then the mayor of Peterborough turned up at the barracks offering homes to 10 families on a new estate. Three months later Quan moved north. Then came school, English lessons and cultural adjustments.

“I remember going down the corridor with one of the girls, chattering away in Cantonese. The deputy head – I was petrified of her – stopped us and said: ‘No, no, no, you should be speaking English in school.’ My dad found a job at a textile company owned by a Greek family. He would open up the factory first thing in the morning. At one point he spoke English with a Greek accent.” Quan speaks with an unmistakable London accent.

The Nguyen brothers have retained a Vietnamese inflection to their English as well as a disposition for finding humour in even the most difficult circumstances. Hung Nguyen was sent off to a school near Kensington barracks where he remembers a teacher called Elizabeth. “She taught us to use a fork. We’d never seen one. It looked dangerous. Why would you stick it in your mouth? So we used spoons. After that they hid all the spoons. We stuck the knives in our mouths quite happily, but not forks.” He described his school as “very rough” and said: “We had to learn English and we also learned maths because it was the only thing we could do without fluent English.”

This was the 1970s, when the National Front and casual racism loomed large in Britain. “We had all the usual taunts walking to school – racist names,” said Quan. “I’d hear stories from my mum all the time. The adults themselves felt it more keenly. They found it really hard.”

Others among the Wellpark refugees said they regularly found themselves in fights with racists at school or on the streets of the council estates where they lived. Some of the adults struggled with a new language and found only irregular work far below the professional positions they had once held. But, in time, their children thrived.

Within a few weeks of arriving at Kensington barracks, Hung Nguyen landed a job with a project distributing second-hand books to developing countries. It was run by Lady Ranfurly, later famed for her extraordinary wartime diaries, To War With Whitaker. She offered to help Hung resume his medical studies. “She was an older lady,” he said, “Classy. I was cocky. I turned it down because I wanted to do it on my own.”

The British Council for Refugees gave Hung a scholarship to study English in Saffron Walden. In the holidays he went on a trip with his mother to visit relatives in America. They encouraged him to apply for medical school there and he was accepted. “So I stayed,” he said. “I became a foreign student from England,” he added, laughing at the thought. After his medical degree, he studied for an MBA and in time did well out of the considerable overlap between medicine and business in the US.

Today, Hung Nguyen owns an entire block in an area southeast of Los Angeles known as Little Saigon, home to the largest gathering of Vietnamese outside their home country. It holds his medical practice, a dentist’s office and a chemist. His company is named Wellpark Inc and, outside, he is building a memorial to the ship that rescued him. Hung also hosts a weekly medical phone-in on local radio in Vietnamese.

“Sometimes I talk about the Wellpark. I say: ‘There are people who helped us who some of them forget. They don’t even remember. They don’t realise how much impact what they did had. But we remember and we might never be able to pay them back, but we can pay it forward. We can help other people in their honour.’”

A decade after he moved to California his parents followed and opened a launderette. About a dozen of the Wellpark families settled in the US. The bulk remained in Britain, including Huy. He took a degree in civil engineering after calling the University of Manchester and asking to be put through to the engineering department.

“They said: ‘What engineering?’ I said: ‘I don’t know, give me any.’ So they connected me to civil engineering. They said: ‘You sure you know what civil engineering is?’ I didn’t know, but I didn’t want to admit it. So I said: ‘Yeah, I know.’ I ended up doing civil engineering. I love it.” Huy is now a consultant for Transport for London, modelling how to manage the city’s traffic – overground, underground and on the river.

Diep Quan studied for a degree in business and accounts. “I’m one of Thatcher’s children. Business. Got to go make money. Still didn’t know what I wanted to do. I just knew that was the stepping stone to get to where the money is.” Today, she works as an IT trainer on contract to Morgan Stanley.

Over the years Hung Nguyen wondered what had become of the Wellpark’s crew and his fellow refugees. He helped organise a 30th- anniversary reunion in 2008 in Little Saigon. Captain Connell went. So did Holmes, returning the ring to Luisa Van Nu.

Hung took his four children, then aged 10 to 16. “I told them: ‘If it wasn’t for these people you wouldn’t be here. None of us would be here.’

“We were lucky. We should be dead now. There were 346 people on that boat. Now we’ve multiplied to the thousands. We had kids and our kids had kids. Looking at the pictures from the ship, sometimes I cry, by myself so people don’t see.”

Back to business: Dr Hung Nguyen, who now lives and works in Los Angeles, with his family. Photograph: Barry J Holmes/The Observer

After the success of the California reunion, Quan organised a follow-up in London five years later. “Growing up in Peterborough I’d often wonder where the crew were now,” she said. “It was a very emotional event to meet all these people at last. For us, they were heroes. We wanted to show them our children. We wanted to say: ‘Look, they wouldn’t be here if you hadn’t been there for us.’ It was a huge thing that they did. They could have chosen to turn a blind eye like the other ships. But they didn’t and they risked a lot to rescue us.”

Holmes said he was uncomfortable at the outpouring of emotion from the survivors. “The MBE didn’t sit comfortably at all with Hector Connell,” he said. “He didn’t think of himself as a hero. None of us did. The reunion was at a restaurant in Little Saigon. They presented me with a glass with a map of the South China Sea: ‘In appreciation of your heroic and humane act for giving 346 people a second chance in life.’ I told them anyone would have done the same thing. We just happened to be there at the time. But they wouldn’t hear it.”

The reunion was also a chance for the Wellpark refugees to compare the different paths their lives had taken since the rescue. A consensus emerged that the US was the place to end up if you wanted to make money, but that Americans spent too much time working. Hung Nguyen, who has become a millionaire and drives a Mercedes-Benz, said he sometimes envied his brother Huy’s lifestyle in London. “Life there is much better. Here in America we work very hard. He has long vacations, goes on holiday to the Philippines with his wife. It kills me.”

Huy has no regrets about staying in London. “The British gave me everything – it’s now my time to pay back,” he said, speaking after a day of jury duty at Croydon Crown Court. “When I pay tax I don’t complain.”

Few of the people rescued by the Wellpark imagined ever returning to Vietnam, but in recent years the country has opened up and many of the thousands who fled have visited their homeland. They recount similar experiences of being stunned by the scale of change and the difficulty of finding former homes.

Hung Nguyen has gone back to Vietnam twice. “They’re not communists any more. They’re capitalists! We call them red capitalists. Lots of rich people. Filthy rich. Lots of poor people.

“I went to visit my friends from high school. They all looked a lot older than I do. We’re the same age, but it’s a harder life there for them.”

Paul Tran was four years old when he was rescued by the Wellpark and had no memory of Vietnam. But he has returned repeatedly and developed a close attachment to the country he was born in. “My parents left the country because of that regime. Yet I’m going back of my own choice to understand my roots a bit better and meet guys about the same age as me and hear their stories and histories. I keep going back because I like our culture. I like our country. I’ve had thoughts about whether it would have been better if my family had stayed. But I’m comfortable in my own skin here. I could have been a right dickhead over there. I could have been a spoilt kid, I could have been a gangster. Now I’m well British, but with a Vietnamese culture.”

Quan organised an extended family holiday to her birthplace in 2012. Eighteen people, including her husband and their daughter, who had never been to Vietnam, travelled around the city she knew as Saigon in a minibus. She said that by the time the visit was over she knew she belonged in London more than Vietnam, even if that was her history. But she suspected her father felt differently.

“I think my dad never wanted to leave,” said Quan. “He lost everything. I think it broke him in lots of ways. I don’t think he ever recovered from it. Not just from a money perspective. I think it broke him as a person.

“My sisters say: ‘We’re the age our dad was when he left. What if I now had to lock my front door and get on the boat and head down the estuary? Don’t know where I’m going, but I can’t stay here.’ What would make you so afraid? What would scare you so much that you would do that? You lose everything. It’s quite hard for someone to imagine that.”

Which is why the flow of refugees from Syria to Europe has resonance for the former boat people. “I cried when I saw the news about Germany taking all those refugees,” said Huy. “I was quite surprised they were that open to that many people. I was really moved by what the Germans did. I think the British could have done more.”

Quan is frustrated by what she describes as a lack of compassion for the Syrians, even if she understands it is at least in part driven by fear of terrorism.

Tran said he saw himself in the pictures of Syrians marching across Europe. “When I saw the footage, I put myself in their position because I was in that sort of position. I started having all these questions. Were they forced to leave? Were they kicked out? And then I thought, were we forced to leave? No. It was our choice to leave. And I thought, ‘Maybe for some it was their choice to leave and maybe others had no choice because of war,’” he said. “What do I feel? It’s like what most humans would do. They’re very desperate people to want to leave. Like our families were.”

Vietnam: the exodus

Two million people fled Vietnam between the end of the war in 1975 and the opening up of the country in the mid-1990s. Almost 800,000 left by sea, most headed for Hong Kong, Malaysia or Indonesia. Widely known as ‘boat people’, the majority left in the late 1970s, often not surviving the treacherous journey because their boats sank or were attacked by pirates. Those people who reached land usually found themselves in refugee camps, as other countries in southeast Asia were reluctant to accept them. The majority were eventually taken in by the US, though Australia and Canada also welcomed substantial numbers. Although the boat people never expected to return to Vietnam, at least while the communist government was in power, many have since visited their homeland. Katie Forster