British Citizen

British nationality law is the law of the United Kingdom which concerns citizenship and other categories of British nationality. The law is complex due to the United Kingdom's historical status as an imperial power.

English law and Scots law have always distinguished between the Monarch's subjects and aliens, but British nationality law was uncodified until the British Nationality and Status of Aliens Act 1914 codified existing common law and statute, with a few minor changes.

Some thought the single Imperial status of British subject as increasingly inadequate to deal with a Commonwealth with independent member states. In 1948, the Commonwealth Heads of Government agreed that each member would adopt a national citizenship (Canada had already done so), but that the existing status of the British subject would continue as a common status held by all Commonwealth citizens.

The British Nationality Act 1948 established the status of Citizen of the United Kingdom and Colonies (CUKC), the national citizenship of the United Kingdom and colonies on 1 January 1949. Until the early 1960s there was little difference, if any, in UK law between the rights of CUKCs and other British subjects, all of whom had the right at any time to enter and live in the UK.

Independence Acts, passed when the remaining colonies were granted independence, contained nationality provisions. In general, these provisions withdrew the status of CUKC from anyone who became citizens of the newly independent country, unless one had a connection with the UK or a remaining colony (e.g. through birth in the UK). Exceptions were sometimes made in cases where the colonies did not become independent. (Notable cases include Penang and Malacca, which were made part of the Federation of Malaya; and Hong Kong, which became part of the People's Republic of China: CUKC status was not withdrawn from CUKCs from Penang and Malacca, and a new British nationality status was created for Hong Kong.)

...
Wikipedia