The Sabor, in its various forms, has represented the identity and opinions of Croats from the diets of the 9th century nobility to the modern parliament. The oldest Sabor whose records are preserved was held in Zagreb on 19 April 1273 as the "Congregatio Regni totius Sclavonie generalis" or "Universitas nobilium Regni Sclavoniae" (General diet of the entire kingdom of Slavonia or Community of the nobility of the kingdom of Slavonia). Its decisions had legislative power. The 1527 Parliament decision was a decisive event of fundamental importance for the extension and confirmation of Croatian statehood, as described by the Constitution of Croatia. The parliament freely chose Ferdinand I of the House of Habsburg as the new ruler of Croatia, after centuries of Croatian personal union with Hungary. Following the entry into the Habsburg Monarchy, the Sabor became a regular noble diet, and its official title gradually stabilised by 1558 to the Parliament of the Kingdom of Croatia and Slavonia. Since 1681 it has been formally styled as the "Congregatio Regnorum Croatiae, Dalmatiae et Slavoniae" or "Generalis Congregatio dominorum statuum et ordinum Regni" (Diet of the Kingdom of Croatia, Dalmatia and Slavonia or General Diet of the Estates of the Realm). In 1712, the Sabor once again invoked its prerogative to select the ruler, supporting what later became the Pragmatic Sanction of 1713 and electing Maria Theresa of Austria as monarch. This event is also specified by the Constitution of Croatia as a part of the foundation of unbroken Croatian statehood from the Middle Ages to the present.