Embassy of the United States to the Holy See to the Holy See, previously located on Aventine Hill, moved to new headquarters in September 2015 in a separate building on the same compound as the United States Embassy Rome. Embassy of the United States to the Holy See The Embassy of the United States of America to the Holy See (or Embassy Vatican for short) is the diplomatic mission of United States of America to the Holy See, a term referring to the central government and universal reach of the Roman Catholic Church. The current embassy moved to new headquarters in September 2015 in a separate building on the
Foreign relations of the Holy See between countries, including a dispute between Germany and Spain over the Caroline Islands. The Lateran Treaty of 1929 and the founding of the Vatican City State was not followed by any great immediate increase in the number of states with which the Holy See had official relations. This came later, especially after the Second World War. The Holy See, as a non-state sovereign entity and full subject of international law, started establishing diplomatic relations with sovereign states in the 15th century. It had the territory of the States of the Church under its direct sovereign rule since centuries before that