information:highlighting
Under Italian rule (1871–1929)

In 1870, the Pope's holdings were left in an uncertain situation when Rome itself was annexed by Italian forces, thus bringing to completion the Italian unification, after a nominal resistance by the papal forces. Between 1861 and 1929 the status of the Pope was referred to as the "Roman Question".

Italy made no attempt to interfere with the Holy See within the Vatican walls. However, it confiscated church property in many places. In 1871, the Quirinal Palace was confiscated by the King of Italy and became the royal palace. Thereafter, the popes resided undisturbed within the Vatican walls, and certain papal prerogatives were recognised by the Law of Guarantees, including the right to send and receive ambassadors. But the Popes did not recognise the Italian king's right to rule in Rome, and they refused to leave the Vatican compound until the dispute was resolved in 1929; Pope Pius IX (1846–1878), the last ruler of the Papal States, was referred to as a " prisoner in the Vatican ". Forced to give up secular power, the popes focused on spiritual issues.