It followed the Act of Settlement 1701, whereby Dowager Electress Sophia of Hanover and her Protestant descendants were declared to be in the line of succession to the throne (her son George I later became king).

This was first tested between 1955 and 1957 when Prince Ernest Augustus of Hanover successfully claimed British nationality on this basis[2][3] after considerable litigation.

[4] As he was born and was a Protestant while the Act was in force, the courts recognized that he had already acquired citizenship, which the repeal of the statute did not affect.

Alexander, Crown Prince of Yugoslavia was also given British citizenship using the Sophia Naturalization Act.

[5] In the present time, however, most people likely to successfully claim citizenship in this manner would obtain the status of British Overseas citizen.