[QUOTE=rayh]
According to this wikipedia article, the heir to the throne must be Protestant to succeed to throne. According to some interpretations if the heir has ever been Catholic they cannot succeed, although other interpretations allow for conversation before the death of the reigning monarch.
[/QUOTE]
Wikipedia is wrong. There is no ambiguity at all on this point. The Act of Settlement makes it clear that those persons who have been Catholics are ‘excluded and are by that Act [the 1689 Bill of Rights] made for ever incapable to inherit possess or enjoy the Crown and Government of this Realm’ (emphasis added). This is consistent with the ‘once a Catholic, always a Catholic’ prejudices of the late seventeenth century. One particular fear was that a Catholic candidate might casuistically pretend to convert in order to claim the throne. The Act was therefore carefully worded to avoid that possibility.
[QUOTE=Giles]
The last forced abdication was in 1688 – the “Glorious Revolution” when the Catholic King James II and VII was forced to leave the kingdoms of England and Scotland, and the Protestant Stadtholder of the Netherlands invited to come and replace him.
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And 1688 almost - but not quite - provides one possible precedent for someone ceasing to be Prince of Wales etc., in that James II’s newly-created Prince of Wales, his son, James Francis Edward (the ‘Old Pretender’), ceased to be the heir to the throne when James II was deposed.
Except that William III and Parliament just fudged this particular issue. Instead of having to decide whether he was still the Prince of Wales, they sidestepped the difficulty by querying whether he had been so in the first place, or indeed whether he was James’s son. Not the most elegant or legal of solutions, but one that was, in the circumstances, sufficient for their purposes.