The Perth Agreement was made in Australia in 2011 by the prime ministers of the sixteen states known as Commonwealth realms, which at the time all recognised Elizabeth II as their head of state. The document agreed that the governments of the realms would amend their laws concerning the succession to their shared throne and related matters. The changes, in summary, comprised: The ban on non-Protestants becoming monarch and the requirement for them to be in communion with the Church of England was not altered.