Posted 07 October 2008 - 06:33 PM
Henry married Katherine of Aragon because he was told to. His father wanted an alliance with Spain. He had got it by marrying his eldest son Arthur to KoA, but thenArthur had got TB and died. KoA was still kicking around in England, so they did the obvious thing and - since the marriage between Arthur and KoA had not been consummated (ie she was still a virgin) - married her to Henry.
The reason he wanted rid of KoA was because he needed a male heir and KoA could not give him one. She got pregnant 17 times, but not one of them lived.
(He had also fallen for Anne Boleyn, but I really do believe that was a secondary factor.)
So alot of the reasons he gave for getting rid of KoA were a case of just saying anything until something worked. The idea that henry put most emphasis on was his claim that KoA's marriage to Arthur HAD been consummated, that he had therefore married his dead borther's wife (which was forbidden in the Bible). That was why, he said, his marriage was cursed.
The Pope would normally have garnedt a request like that without a thought BUT KoA was the aunt of the humongously-powerful Charles V, King of Spain AND Holy Roman Emperor. In 1525 (check the date - I'm just doing it from memory), Charles had conquered Rome, sacked the city, and had the Pope virtually under house arrest. Pope Clement took one look at the troops outside and decided he's rather upset Henry than Charles.
It was Cromwell and Cranmer who suggested that, if Henry made himself head of the Church, he could give himself a divorce.