Current British royal family is entirely German, from House of Hanover and Battenberg. No relation to House of York or Lancaster.
Wasn’t George I the great grandson of James I?
Darling: [desperate] Ah! No, no, no, wait! No, look, I'm English! I was born in Croydon! [breathing heavily] I was educated at Ipplethorpe Primary School! I've got a girlfriend called Doris! I know the words to all three verses of "God Save the King!"
Blackadder: Four verses!
Darling: Four verses! Four verses! I meant four verses! Look, I'm as British as Queen Victoria!
Blackadder: So your father's German, you're half-German and you married a German?!