PILCOMAYO, APOSTOLIC VICARIATE OF. - The mission of P., situated in the north-western part of Paraguay and the south-western part of Bolivia, was erected as a prefecture on 26 February 1925 with territory detached from the apostolic vicariate of the Chaco in Bolivia.
At that time the prefecture was in Bolivian territory, but in 1938 it became Paraguayan owing to the fact that almost all of its territory was included in the immense Bolivian region awarded in that same year by the Treaty of Buenos Aires to Paraguay following the last war between the two Republics. By decree of May 12, 1944, Propaganda better defined the boundaries of the prefecture, detaching from it the small area of territory that remained Bolivian, in order to unite it with the vicariate of Chaco, while on the opposite side its limits were extended as far as the right bank of the Paraguay River.

PILEUS - Soldiers with the pileus pannonicus capturing St. Peter. Detail of the so-called dogmatic sarcophagus (4th century) - Rome, Lateran Museum.
(phot. Fides)(from Wilpert, Sarcofagi, pl. 56)
On March 11, 1948, the vicariate of Paraguayan Chaco was erected and entrusted to the Salesians, and in this way the entire Chaco region was definitively organized; in fact, the whole northern part (apostolic vicariate of Paraguayan Chaco) was given to the Salesians, and the whole southern part of the P. was entrusted to the Oblates of Mary Immaculate. On July 14, 1950, the apostolic prefecture of the P. was elevated to an apostolic vicariate. It has an area of 110,000 sq km with a population of around 50,000 inhabitants, of whom 25,000 are Catholics, a few Protestants, and the rest pagans, belonging to the Chulupi, Choroti, Mataco, and Guarayo tribes. Twelve Oblate priests, 10 brothers, and 6 sisters work there. There are 6 principal stations and 6 secondary ones, 1 quasi-parish, 11 churches and chapels in all. Dispensaries 4, boarding schools 5. Elementary schools 5, vocational schools 1. There are also in the mission some lay religious confraternities.
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Antonio Mazza