What then of Victoria and Albert who were 1st cousins?
CC
England had already broken with the Vatican under Henry VIII, and as head of the church of England, he likely made the rules. Catholics were prosecuted, so I’m thinking, the relationship degree probably didn’t matter so much in the new church. There were obviously no restrictions for Victoria and Albert to marry unless it had to be approved by someone like the the Archbishop of Canterbury. The marriages of Louis VII of France, and Henry II of England to Eleanor of Aquitaine were approved by the Pope.
It would be interesting to see if, and when the concern about marrying close relations changed again. I’m assuming they reverted back to some restrictions, especially with the advancements in science and genetics.
The Hapsburgs have joined the chat.