the title Emperor of India, although remaining head of state of the Dominion of India. At first, every member of the Commonwealth retained the same monarch as the United Kingdom, but when the Dominion of India became a republic in 1950, it would no longer share in a common monarchy. Instead, the British monarch was acknowledged as "Head of the Commonwealth" in all Commonwealth member states, whether they were realms or republics. The position is purely ceremonial, and is not inherited by the British monarch as of right but is vested in an individual chosen by the Commonwealth heads of government. Member states of the Commonwealth that share the same person as monarch are informally known as Commonwealth realms. Monarchy in Ireland In 1155 the only English Pope, Adrian IV, authorised King Henry II of England to take possession of Ireland as a feudal territory nominally under papal overlordship. The Pope wanted the English monarch to annex Ireland and bring the Irish church into line with Rome, despite this process already being underway in Ireland by 1155. An all-island kingship of Ireland had been created in 854 by Máel Sechnaill mac Máele Ruanaid. His last successor was Ruaidrí Ua Conchobair, who had become High King of Ireland in early 1166 and exiled Diarmait Mac Murchada, the King of Leinster, a vassal kingdom. Diarmait asked Henry II for help, gaining a group of Anglo-Norman aristocrats and adventurers, led by Richard de Clare, 2nd Earl of Pembroke, to help him regain his throne. Diarmait and his Anglo-Norman allies succeeded and he became King of Leinster again. De Clare married Diarmait's daughter, and when Diarmait died in 1171, de Clare became King of Leinster. Henry was afraid that de Clare would make Ireland a rival Norman kingdom, so he took advantage of the papal bull and invaded, forcing de Clare and the other Anglo-Norman aristocrats in Ireland and the major Irish kings and lords to recognize him as their overlord. By 1541, King Henry VIII of England had broken with the Church of Rome and declared himself Supreme Head of the Church of England. The Pope's grant of Ireland to the English monarch became invalid, so Henry summoned a meeting of the Irish Parliament to change his title from Lord of Ireland to King of Ireland. In 1800, as a result of the Irish Rebellion of 1798, the Act of Union merged the