(A note on the data: this map uses 2011 Census figures for foreign-born residents compiled by the Migration Observatory. That means a couple of things. First, the picture will have changed since these figures were compiled, but they're still the best national-level data around. And second, "foreign-born" includes many different sorts of people, including the children of expat Brits who then come home. They wouldn't fit some common definitions of "immigrant", but again, they're probably the best stats available.)