The Council of Trent is one of the most important events in the history of the Roman Catholic church. It was convened at Trent, now in northern Italy, from 1545 to 1563—with several breaks in between--with the twofold task of defining the doctrines of the church in reply to the heresies of the Protestants and of bringing about a thorough reform of the inner life of Christians. The Canones et decreta make no attempt at embracing the whole doctrinal system of the Roman Catholic church; instead, they present a selection of the most vital doctrines chosen to counter Protestantism.
There was a keen interest throughout the Catholic world in the proceedings and conclusions of the council. As early as 1548, the need to publish and disperse the proceedings and decrees of the council was clear. The official publication of the decrees fell to Paulus Manutius at Rome. In addition, Paulus promised to write and publish a complete history of the Council of Trent. Unfortunately, he was never able to compile this ambitious project which, like many other of his plans, was undoubtedly swallowed up by the demands and pressures of managing the press in Rome, an enterprise which detracted increasingly from his own scholarly pursuits.