The Council of Trent was one of the Roman Catholic Church's most important ecumenical councils. The Council met for twenty-five sessions between December 13, 1545 and December 4, 1563, all in Trento, apart from the ninth to eleventh sessions held in Bologna during 1547. Pope Paul III convoked and presided over the first eight sessions (1545-47). During the sessions the Council issued key statements and clarifications of the Church's doctrine and teachings, including condemning the principles and doctrines of Protestantism and addressing scripture, the Biblical canon, sacred tradition, original sin, justification, salvation, the sacraments, the Mass and the veneration of saints. It was the 19th overall recognized council by Roman Catholic theologians. The next, more than three hundred and fifty years later, was the First Vatican Council (Vatican I).
- Wikipedia: Council of Trent