The Roman Catechism - also called The Catechism of the Council of Trent was commissioned by the dogmatic Council of Trent to expound Catholic doctrine and to improve the Theological understanding of the clergy.

Protestantism had just broken out with Martin Luther in Germany and King Henry VIII in England in addition to other reformers such as John Calvin and so it was important to safeguard against the possibility of priests falling into heresy.  Originally written in Italian and published 1566.  This catechism was subsequently translated into Latin (the official language of the Catholic Church) and subsequently translated into the vernacular of every country.

It can be read in the English language on-line by clicking here.