By Huong Phan
BBC Vietnamese Service
As the North Vietnamese army took control of Saigon 30 years ago, thousands of South Vietnamese began travelling the other way.
Thousands fled Saigon when the North Vietnamese arrived
It was the beginning of a huge exodus.
Today there are approximately three million Vietnamese scattered around the world, with more than a third of them gathered in the United States.
Little Saigon in Orange County, southern California, is their unofficial capital.
Today the enclave's Phuoc Loc Tho Shopping Centre is a bustling place where Vietnamese music and the smell of Vietnamese food punctuate the air.
It is hard to believe that two decades ago, this area was full of strawberry fields and orange groves.
Tough first years
The first wave of Vietnamese who came to America were put into four main holding camps.
After being allowed out, they found jobs and homes in the surrounding area.
The first years were hard. Tony Lam, one of the émigrés, said he still sheds tears when he remembers the days his wife returned from her factory job producing musical instruments.
She was so white from the dust that he could hardly recognise her, he said.
Kiem Le, now a successful chief executive at a hi-tech company in San Diego, said his own day at that time started at 0400, so he could arrive at work exactly on time at 0700. He never finished until late at night.
But from such beginnings, the Vietnamese community in the US grew in leaps and bounds.
Nowadays, even though the community's per capita income is still 40% lower than the national rate, its average household income is almost the same - an indication of the strength of the family unit.
The community has also started to demand a voice in politics. Its first effort was a campaign to commission signs in the neighbourhood bearing the name of Little Saigon, which are now visible on all major highways in the area.
Phung Minh Tien, one of the campaigners, said the name was officially recognised by the state of California in 1988.
From local council to state assembly, the community has started to be represented.
Compared with that of other Asian immigrants, the Vietnamese community is highly politicised, according to Do Qui Toan, a local journalist.
"Whereas the older generations demonstrate against the government in Vietnam, demanding freedom for the homeland, the younger generations prefer to join mainstream politics and have a voice on taxation or health insurance policy," he explained.
The community's growing economic strength also means that many Vietnamese in the US are now courted by the nation they left behind.
But often they find it hard to reconcile themselves with their erstwhile homeland.
Phuoc Loc Tho Centre evokes sights and smells of Vietnam
Political ideology and personal memories of the war make it difficult for them to see Vietnam in a positive light.
But as local architect Andy Dzung pointed out: "We must find a way to accommodate ourselves, now that the US and Vietnam have established both diplomatic and trade relationships, for otherwise we cannot take advantage of this new development."
Furthermore, underneath the facade of prosperity, the Vietnamese community in the US suffers from deep psychological and social problems - problems which only healing the rift with the place they came from might be able to assuage.
"We did not come here the way other migrants came," said social worker Phung Minh Tien.
"They came to paradise to realise their personal dreams. We were like trees uprooted and planted in a foreign land," he said.
Yet those trees have now recovered and are growing strong.
The first 30 years were devoted to survival. Who knows what the next 30 years will bring.