Landing at Luanda’s Quatro de Fevereiro International airport is rarely a pleasant experience. The immigration queues are long and slow, the boothed officers gruff, and it always seems to take an age for your luggage to creak its way into the sweaty and overcrowded arrivals hall.

Several security checks later, you are finally allowed outside into the humidity. Here the honking traffic jams await you, ready to sap your energy and leave you ill-prepared for the surly receptionist at your overpriced hotel, where the internet is slow and the air-conditioning faulty. Luanda can be one of the most unwelcoming places on Earth – as well as the most expensive – and yet this has not deterred thousands of Portuguese people from packing their bags and heading south to escape the Eurozone recession.

There are now around 100,000 Portuguese nationals officially living in Angola – up from 21,000 in 2003 – but the real figure is likely to be much higher. That so many Portuguese are now clamouring to get to Angola at any cost – when it was only a little over a decade ago that Angolans were the ones scheming to get out of their war-ravaged country and into Europe – says as much about how low Portugal has slumped as how Angola has risen. “There are so many more opportunities here than there are in Portugal right now,” says Diana Cordovil Espada, who moved from Lisbon to Angola in 2009. “Angola is an exciting adventure, whereas Portugal is depressing. You can earn more in Angola than you can in Portugal and promotion is faster. Everyone wants to come here. It’s all people are talking about at home and lots of my friends are sending me their CVs to see if I can get them jobs.”

This new wave of migration is, in some ways, a modern version of earlier exoduses that began back in the 15th century with explorers Vasco da Gama and Bartolomeu Dias, whose voyages to India and Southern Africa laid the foundations for Portugal’s four-continent colonial footprint.

In the 20th century, under the fascist dictatorship of António de Oliveira Salazar, thousands of Portuguese were sent to populate African colonies – both as low-level labourers and well-paid professionals – while many simply fled elsewhere of their own accord from the repressive regime and faltering economy.

Portugal’s prime minister, Pedro Passos Coelho, who has told Portuguese graduates to “get out of their comfort zone” and find work abroad, spent his early childhood in Angola before independence in 1975, when the Portuguese left en masse.

Pedro Seabra, a researcher at Lisbon-based think-tank the Portuguese Institute of International Relations and Security, says: “The Portuguese as a nation have always had a tradition of migration. They go where the opportunities are. In the 1960s it was to the US and Europe, and now it is to Brazil, Mozambique and Angola.”

Unlike recession-struck Portugal, where unemployment has tipped 15 per cent, Angola has been enjoying an oil-driven economic boom since 2002 and the end of its three-decade civil war. Thanks to the shared language and similar legal system, Portuguese companies have found operating in Angola easier than their Anglophone or Francophone competitors, thus cornering a niche.

Bilateral trade in 2011 was valued at just over €3bn – Angola is Portugal’s fourth biggest destination for exports and its largest outside the European Union – and this has created a firm platform for Portuguese job opportunities in the country. Portuguese construction firms such as Teixeira Duarte, Somague, Mota-Engil and Soares da Costa have done extremely well out of Angola’s post-war rebuilding programme, winning lucrative government contracts to deliver new roads and buildings and private property deals of the sort that domestically dried up long ago.

A number of Angolan banks – such as Banco de Fomento Angola (bfa), Banco Espírito Santo Angola (Besa) and Millennium bcp – have links to Portuguese financial institutions, while Portuguese lawyers, accountants and architects are in demand to fill positions in a country grappling with skills shortages. Much of the food in Luanda’s supermarkets comes directly from Portugal, as do the pharmaceuticals, toiletries, books and furnishings. In fact, there is so much of Portugal in Angola – the beer, wine, television and football teams, too – that you could forget you are in Africa.

Except that you never will, because despite Angola’s impressive economic growth, social development has been painfully slow. Luanda’s glass and steel skyline, best viewed at sunset sipping cocktails from the yacht club restaurants across the bay, tells only a tiny part of Angola’s story. The gdp may have skyrocketed but it’s been slim pickings for the majority of the population, who live in poverty without access to water or electricity. Schools are over-subscribed and teachers poorly qualified; hospitals are understaffed and rarely have medicines; and in the sprawling and crowded slums, where most people live in self-built homes, there are few paved roads and sanitation is a luxury.

“The war has been over for 10 years and the economy is booming, but very few people are benefiting,” says Paula Cristina Roque, an Angola expert at Oxford University. “The money from oil is not trickling down to the ordinary Angolan; it benefits a small elite due to high levels of corruption and nepotism.”

Corruption (known as gazosa or saldo) is endemic: from the lowest level, where getting anything done involves coming to an “arrangement” – a fizzy drink or mobile phone credit usually works – right up to the very top, where billion of dollars in oil revenues have allegedly gone missing over the years.

Some people are getting rich in Angola but most are not; the stark inequalities between the haves and the have-nots are visible everywhere in Luanda. Beggars in torn rags sit slumped on the crumbling pavements next to bmw and Porsche dealerships; outside the capital’s beachfront restaurants – where a meal for two without drinks will easily set you back €160 – barefoot children congregate, demanding tips to help you park.

In an even more ironic twist, the former colony is now taking controlling stakes in the economy of its one-time oppressor. Not only are the Angolan elite among the biggest spenders in Lisbon’s boutiques but their parastatals and private businesses have started acquiring shares in major Portuguese firms such as Galp Energia and Millennium bcp.

The eldest daughter of long-serving president José Eduardo dos Santos, Isabel, is often described as Portugal’s most influential businesswoman. She has already snapped up the failing Banco Português de Negócios (bpn) through her part ownership of Angolan high-street operation Banco bic. This adds to a portfolio that includes shares in Galp, Portugal Telecom and Sonae, which will shortly launch the Continente Supermarket chain in Angola.

Angolan journalist and anti-corruption campaigner Rafael Marques de Morais isn’t happy with what he sees. He accuses Angolan businessmen and government ministers of using Portugal to launder their “ill-gotten gains”. “Portugal has never been a true ally of Angola,” he says. “Not during colonial times, not during the war when it armed different sides and not now, when it is too busy exploiting us to care for the corruption and suffering of the people.”

Few of the Portuguese in Angola discuss the politics of the country they are living in. While some are specifically told by their employers not to, others say it is not their place and that they feel they can better contribute by sharing their skills and helping the country develop, rather than taking sides or expressing opinions.

But as the number of Portuguese working in Angola continues to rise, so does resentment towards them. Luis Joao works for a car-hire company in Luanda and often picks up tugas, as he calls them, taking them from the airport to their all-expenses-paid guesthouses, where they will be given a car and driver for the duration of their stay in Angola.

“We used to be ok with the Portuguese,” says the 32-year-old, who lives in a slum without water and only sketchy electricity. “We used to see them as a wealthy nation who had things to share with us. But now we know they are poor, so why are they still treated like royalty? Why don’t we train up Angolans to do the jobs they are doing?”

Marcos Fernandes, who relocated to Luanda in March to work for a Portuguese-run chain of pharmacies, says, “There is some resentment towards us – that we are coming here and taking jobs when so many Angolans are out of work. Crime is definitely going up and the police are a real problem, too. I am stopped all the time because I am white and Portuguese. They are looking for problems with my car or paperwork in order to get a bribe.”

But Fernandes, whose grandfather worked in Angola in the 1960s, says it’s worth it. “It’s something I’d wanted to do for a long time. Even though you’re in Africa you don’t feel too far away. There are many other Portuguese people, you can eat Portuguese food and watch Portuguese television. I feel at home.”