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In OTL Henry VIII is famous for the messy divorce of his first wife Catherine of Aragon (so messy it involved the removal of her head). He wanted a divorce with Catherine but that went against the Catholic church, so Henry sent an English cardinal to negotiate with the Pope to allow the divorce. At the first part of the meeting things were going pretty well and the Pope was almost certainly going to allow it. But Cardinal Wosley had decided to bring his greyhound along for the trip, when the meeting was over and Wosley bent over to kiss the Pope's feet the Greyhound thought it looked like his master was about to get kicked in the head so he attacked the Pope and bit him several times. The Pope was furious and refused the divorce, basically inventing Protestantism and starting countless wars.
Lets say Cardinal Wosley is more of a cat person, and suffices to bring his tabby Mr.Tibbles rather than an over-protective greyhound. The divorce goes as planned and Protestantism is never invented.
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