The House of Hanover
The House of Hanover is a German royal house and the current British royal family is regarded as being German because they are descendants of the House of Hanover.
It was when Queen Anne (who was the last of the Stuart monarchs) died and the Act of Settlement 1701 forbid a Roman Catholic from inheriting the throne, that the throne passed to the Stuart’s German Protestant cousin – George Louis of Brunswick-Luneburg (Hanover) - hence King George I became the first Hanoverian King of Great Britain and Ireland. The House of Hanover came to an end with the death of Queen Victoria.
The current head of the House of Hanover is Ernst August, Prince of Hanover (husband of Princess Caroline of Monaco) who is the senior male descendant of King George III.