In the Commonwealth realms, a Royal Style and Titles Act is an Act of Parliament passed in the relevant jurisdiction which defines the sovereign's formal title in that jurisdiction. The most significant of these acts is the Royal and Parliamentary Titles Act 1927 of the United Kingdom, which recognised the creation of the Irish Free State, a development that necessitated a change in King George V's title. In December 1952, the governments of Commonwealth realms agreed that each realm would adopt its own royal titles.