The numbers for Czech-born people are among those to be treated with caution because of a rapidly changing situation.
Firstly, the Czech and Slovak republics have produced large numbers of Roma-Gypsy refugees in the five years since the 2001 Census.
Today, both countries are new EU members whose citizens can work elsewhere in Europe. But before accession some of the workers were almost certainly among the undeclared working in the 'black' economy.
Further back a different refugee movement formed a prominent group of Czechs in Britain: Jewish children brought over to escape the Nazis in the 1930s.