Embassy of the United States to the Holy See 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 same compound as the United States Embassy Rome. The embassy was previously located on Aventine Hill in the Villa Domiziana in Rome, Italy, which was built as a private residence
Holy See former Secretary for Relations with States, said that the Vatican City is a "minuscule support-state that guarantees the spiritual freedom of the Pope with the minimum territory". The Holy See, not the Vatican City, maintains diplomatic relations with states. Foreign embassies are accredited to the Holy See, not to the Vatican City, and it is the Holy See that establishes treaties and concordats with other sovereign entities. When necessary, the Holy See will enter a treaty on behalf of the Vatican City. Under the terms of the Lateran Treaty, the Holy See has extraterritorial authority over various sites in Rome