Peter Canisius (1521 – 1597) was a renowned Dutch Jesuit Catholic priest. He became known for his strong support for the Catholic faith during the Protestant Reformation in Germany, Austria, Bohemia, Moravia, Switzerland and the British Isles. The restoration of the Catholic Church in Germany after the Protestant Reformation is largely attributed to the work there of the Society of Jesus, which he led.  He is also known for adding the sentence: “Holy Mary, Mother of God, pray for us sinners” to the Hail Mary prayer.

In 1547 he attended several sessions of the Council of Trent. Canisius was an influential teacher and preacher, especially through his “German Catechism”, a book which defined the basic principles of Catholicism in the German language and made them more accessible to readers in German-speaking countries. He was offered the post of Bishop of Vienna in 1554, but declined in order to continue his traveling and teachings. He moved to Germany, where he was one of the main Catholic theologians at the Colloquy of Worms in 1557, and later served as the main preacher in the Cathedral of Augsburg from 1559 to 1568, where he strongly witnessed to his faith on three or four occasions each week. Canisius was renowned as a popular preacher. In 1562 he founded what was to become the University of Innsbruck.

By the time he left Germany, the Society of Jesus in Germany had evolved from a small band of priests into a powerful tool of the Counter-Reformation. Canisius spent the last twenty years of his life in Fribourg, where he founded the Jesuit Collège Saint-Michel, which trained generations of young men for careers and future university studies.  In 1591, at the age of 70, Canisius suffered a stroke which left him partially paralyzed, but he continued to preach and write with the aid of a secretary until his death in Fribourg.  He is venerated in the Catholic Church as a saint and as a Doctor of the Church.