Diplomatically, the Holy See acts and speaks for the whole church. It is also recognised by other subjects of international law as asovereign entity, headed by the Pope, with which diplomatic relations can be maintained.[2][3] Often informally referred to as "the Vatican", the "Holy See" is not the same entity as the "Vatican City State", which came into existence only in 1929 because of theLateran Treaty; the Holy See, the episcopal see of Rome, dates back to antiquity. Ambassadors are officially accredited not to the Vatican City State but to "the Holy See", and Papal representatives to states and international organizations are recognized as representing the Holy See, not the Vatican City State. The creation of the Vatican City state was meant to ensure the diplomatic and spiritual independence of the Pope.
Though all episcopal sees may be considered holy, the expression "the Holy See" (without further specification) is normally used in international relations (and in the canon law of the Catholic Church)[4] to refer to the See of Rome viewed as the central government of the Catholic Church.
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