It always used to be the United Kingdom of Great Britain & Ireland(since Scottish Union in 1707) -

see 'Sic a parcel of rogues for more on that). In c 1921 it was reduced to GB & Northern Ireland.

Soon to be reduced to the UK of Kensington & Chelsea.

Yes Sandman, indeed it was down to the English government that so many Irish emigrated here and to Canada, the US & down under.