Lateran Treaty
Negotiations for the settlement of the Roman Question began in 1926 between the government of Italy and the Holy See, and culminated in the agreements of the Lateran Pacts, signed—the Treaty says—for King Victor Emmanuel III of Italy by Benito Mussolini, Prime Minister and Head of Government, and for Pope Pius XI by Pietro Gasparri, Cardinal Secretary of State, on 11 February 1929. It was ratified on 7 June 1929. The agreements were signed in the Lateran Palace, hence the name by which they are known.
Legal status of the Holy See
For a further group, the legal personality of the Holy See in international law arises from the Lateran Treaty, which, in their view, conferred international standing to the central government of the Catholic Church. In this sense, Oppenheim argued that "the previously controversial international position of the Holy See was clarified as the result of the Treaty of 11 February 1929, between the Holy See and Italy - the so called Lateran Treaty. (...) The Lateran Treaty marks the resumption of the formal membership, interrupted in 1871, of the Holy See in the society of states."