Wacław Hieronim Sierakowski, bishop of Przemyśl, founded a Vincentian house in Brzozów in 1745, which housed a theological seminary for his diocese. The Congregation of the Mission arrived in Brzozów in 1745. There were six priests and two brothers in the house. The bishop invested 78,000 Polish guilders in his estate to furnish his house, and he allocated the income of the parish in Dydnia to the maintenance of the theological seminary. In 1746, the construction of a brick house for the Congregation of the Mission began. The final founding document - both for the Vincentian house and for the diocesan seminary in Brzozów - was issued by Bishop Sierakowski on August 4, 1760. There were always six graduates in the seminary. In addition to the seminary, the house ran a retreat house and a correctional facility for clergy, and organized folk missions in parishes of the Przemyśl diocese. In 1782, the Congregation of the Mission and its headquarters in Brzozów, as well as the local theological seminary in 1783, were liquidated by the Austrian government.