The political and media reaction, meanwhile, was striking for being conducted in only one tone of voice. When politicians of all the main parties addressed the census they greeted the results solely in a spirit of celebration. It had been the same for years. In 2007 the then Mayor of London, Ken Livingstone, spoke with pride about the fact that 35 per cent of people who worked in London had been born in a foreign country.⁴ The question that lingered was whether there was any optimal limit to this or not? For years a sense of excitement and optimism about the changes to the country seemed the only tone appropriate to strike. Bolstered by the pretence that this was nothing new.

Throughout most of its history, and certainly for the previous millennium, Britain had retained an extraordinarily static population. Even the Norman Conquest in 1066 – perhaps the most important event in the islands’ story – led to no more than 5 per cent of the population of England being Norman.⁵ What movement there was in the years before and after was almost entirely movement between the island of Ireland and the countries that would eventually comprise the United Kingdom. Then in the post-1945 period Britain needed to fill particular gaps in the labour market, especially in the transport sector and the newly created National Health Service. And so the period of mass immigration began, though slowly at first. The 1948 British Nationality Act allowed immigration from the former Empire – now the Commonwealth – and by the early 1950s a few thousand people a year were taking advantage of the scheme. By the end of the decade the number of newcomers had gone into the tens of thousands, and by the 1960s the numbers had entered six figures. The vast majority of these arrivals came from the West Indies as well as India, Pakistan and Bangladesh, often entering Britain to do factory work and recommending others – often from their own families or clans – to follow and do similar work in their wake.

Despite some public concern about all this and what it meant for the country, neither the Labour nor Conservative governments that alternated in office were able to do much to stem the movement. As with countries on the continent such as France, Holland and Germany, there was little clarity and less consensus over what the arrival of these workers meant, or even whether they would stay. Only once it became clear that they would stay, and would use the opportunity to bring their extended families to join them, did some of the implications become clear.

During the years that followed there were highly specific Acts of Parliament to address, for instance, criminality among migrants. But there were few attempts to reverse the trend. Even when there was legislation attempting to satisfy growing public concern this had unexpected consequences. For instance the 1962 Commonwealth Immigrants Act, which ostensibly aimed to limit the flow of migrants and persuade some to return home, had the opposite effect, persuading many immigrants to bring their entire families into the United Kingdom while they – as they saw it – had the chance. The fact that Commonwealth immigrants no longer had to have a job to come to after 1962 caused another upsurge. It was not until the 1971 Immigration Act that there was any further attempt to stem the resultant flow. So despite the fact that there had never been any plan to allow migration on such a scale, governments of all stripes found themselves forced to deal with the consequences of the situation in which they and the British people found themselves. It was a situation no one had ever accurately predicted, but which had repercussions that every subsequent government would have to react to.