Lateran Treaty

The 1929 agreements between Italy and the Holy See that recognized Vatican City as a sovereign state and settled longstanding disputes between church and state.

Capture of Rome: The Italian army’s 1870 seizure of Rome from the Papal States, completing Italian unification. It began the territorial dispute the Lateran agreements finally settled.
Vatican City: A sovereign city-state enclosed within Rome that serves as the territorial seat of the Holy See. The treaty established it as an independent state under the pope’s sovereignty.
Vatican City sovereignty: Vatican City’s status as an independent state under the sovereignty of the Holy See. The treaty made this sovereignty internationally recognized.
Separation of church and state: A political principle that distinguishes religious institutions from state authority and limits their institutional entanglement. The Lateran settlement formalized cooperation rather than strict institutional separation.
Roman Question: The dispute over the pope’s status and sovereignty after the Papal States were annexed by Italy. The treaty resolved this conflict between the papacy and the Italian state.
Holy See: The central governing authority of the Catholic Church, headed by the pope. It was the treaty’s counterpart to the Kingdom of Italy.
Roman Catholic Church in Italy: The Catholic Church’s institutions and communities within Italy. The concordat defined the Church’s legal position and public role in Italy.
French law on the Separation of the Churches and the State: A 1905 French law that ended the state’s official recognition and funding of religious bodies. France’s model sharply contrasted with the privileges granted to Catholicism in Italy.
Papal States: A group of territories in central Italy governed by the pope from the eighth century until 1870. Their loss left the papacy without territorial sovereignty until the treaty.
Concordat: A formal agreement regulating relations between the Holy See and a state. A companion agreement set rules for Catholic institutions and religious life in Italy.

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