Basically, the Scots were fighting for their culture: to put a Catholic king on the throne and to keep their ancient clan traditions.
基本上，苏格兰人是在为他们的文化而战：让一位天主教国王登上王位，并保持他们古老的氏族传统。
英语百科
Rex Catholicissimus
The Latin title Rex Catholicissimus, rendered as Most Catholic King and Most Catholic Majesty was awarded by the Pope to the sovereigns of Spain. It was first used by Pope Alexander VI in the papal bull Inter caetera in 1493.
One of the rights of a "Most Catholic" queen – either regnant or consort – is the privilège du blanc, meaning that she may wear white when meeting the Pope rather than the normal black used by other consorts and heads of state.