Holy See
Although the Holy See is sometimes metonymically referred to as the "Vatican", the Vatican City State was distinctively established with the Lateran Treaty (1929) between the Holy See and Italy to ensure the temporal, diplomatic, and spiritual independence of the Papacy. As such, ambassadors are officially accredited to the Holy See and not the Vatican City State. Conversely, Papal nuncios to states and international organisations are recognised as representing the Holy See and the integrity of the Catholic Church along with its 1.3 billion members, not the Vatican City State, as prescribed also in the Canon law of the Catholic Church (1983). The "Holy See" thus refers to the See of Rome viewed as the central government of the Catholic Church. The Catholic Church, in turn, is the largest non-government provider of education and health care in the world, while the diplomatic status of the Holy See facilitates the access of its vast international network of charities.
Old Catholic Church
After the First Vatican Council (1869–1870), several groups of Catholics in Austria-Hungary, Imperial Germany, and Switzerland rejected the Roman Catholic dogma of papal infallibility in matters of faith and morals and left to form their own churches. These were supported by the Old Catholic Archbishop of Utrecht, who ordained priests and bishops for them. Later the Dutch were united more formally with many of these groups under the name "Utrecht Union of Churches".