Following the Capture of Rome on 20 September 1870, the Papal States including Rome with the Vatican was annexed by the Kingdom of Italy. In 1929, through the Lateran Treaty signed with the Italian Government, the new state of Vatican City (population 842) – with no connection to the former Papal States – was formally created and recognized as an independent state. The head of state of the Vatican is the pope, elected by the College of Cardinals, an assembly of Senatorial-princes of the Church. They are usually clerics, appointed as Ordinaries, but in the past have also included men who were not bishops nor clerics. A pope is elected for life, and either dies or may resign. The cardinals are appointed by the popes, who thereby choose the electors of their successors.