Milton Keynes, a new town of 249,000 people some 50 miles from London, is famous among Britons for its American-style road grid, its bright high-modernist shopping mall and an unfortunate sculpture of cows made in concrete and fibreglass. But these pleasant and dull acres of suburbia have become a lot more colourful of late. Competing with the chain stores of the mall, there is now a collection of stalls selling African and Asian food. In the sun of a weekday afternoon, women in multicoloured kaftans gossip in the spacious squares and underpasses. Milton Keynes now has some of the “vibrancy” of multicultural London.

But beneath these broad trends the data reveal a more subtle pattern. In 2001 fully 45% of the minority population of England and Wales lived in London. Now, they are more spread out. As the maps below show, in London ethnic minorities have diffused from inner-city boroughs such as Newham and Tower Hamlets into farther-out places like Barking and Dagenham. Meanwhile, the rest of the country is coming to look more like London: less white, more diverse.

In 2001 around 80% of black Africans in the country lived in London. Now, just 58% do. There have been similar, if smaller, reductions for every other main ethnic group, even those not thought to have dispersed much, such as Bangladeshis. Overall, the ethnic-minority population outside London has increased by 90%, against a more modest rise of 63% in the capital.

In Kent, an affluent county south of London, the size of the ethnic-minority population has grown by 115% since 2001, albeit from a low base. In Hertfordshire, a rural and suburban county north of London, it has doubled. Many of the incomers are moving into Milton Keynes-esque places such as Ashford, in Kent, and Welwyn Garden City, in Hertfordshire. These towns have boxy houses, rational road layouts, plentiful but not especially distinguished greenery, and “herringbone” brick paving. Local politics revolves around blocking development on greenbelt land.

It is not hard to see why ethnic minorities are moving to these towns. There is little crime. Schools are pretty good. Housing is far cheaper than in London, while speedy transport links make it easy to return. The main newcomers are black Africans and Indians from London, as well as Poles, who have settled all over the country since 2004, when the citizens of new members of the European Union were allowed to work in Britain. Similar trends are visible elsewhere. In Solihull, a well-heeled suburban town on the southern fringe of Birmingham, there has been an influx of Indians and Pakistanis since 2001; in less-wealthy Salford, near Manchester, black Africans have moved in.

The flight to the suburbs is changing inner London too. Lambeth, a south London borough, has long been known as the first home of the capital’s black-Caribbean population: the passengers of the Empire Windrush mostly settled there in 1948. But since 2001 black Caribbeans have moved out while Africans have moved in. Shop displays advertise cheap money transfers and phone calls to Ghana and Nigeria. The influx of Africans partly helps to explain why, despite a huge fall in the number of people describing themselves as “Christian” nationwide, Lambeth, together with a few other London boroughs, has managed to increase its tally of the faithful.

Taken with the rapid overall increase in immigrants in the past decade or so, this dispersal may be one reason why immigration has become so controversial. In many of the suburban places migrants are moving to, white British folk are seeing foreign faces in large numbers for the first time. Existing residents often resent the newcomers, who compete for school places, doctors’ appointments and public housing. Politicians are rushing to call for cuts to immigration. On December 12th Theresa May, the Conservative home secretary, denounced “uncontrolled, mass immigration”, which “displaces British workers, forces people onto benefits and suppresses wages for the low-paid”.

But other evidence suggests that most migrants and children of migrants are integrating effectively. The number of people who say they are of mixed ethnicity has almost doubled, from 661,000 in 2001 to 1.2m. According to Sunder Katwala, the director of British Future, a think-tank, mixed couples are now more common in Britain than almost anywhere else, including the United States. And despite the increasing diversity, 91% of people filling out their census form claimed some sort of British national identity, calling themselves English, Welsh, Scottish, Northern Irish or indeed British, sometimes with ethnic additions.

According to the Oxford Migration Observatory, a think-tank, opposition to immigration is weaker in London, where different groups have lived cheek-by-jowl for centuries, than in the rest of the country, even among white-British Londoners. Boris Johnson, its mayor, lauds the benefits of open borders. Contrary to Ms May’s suggestion, growing diversity need not mean lack of cohesion, or strife. Indeed, if the rest of Britain follows London’s path, it may well eventually reduce them.