Pius V was born Antonio Ghislieri in 1504 in Bosco, near Alessandria. He joined the Dominican order as a young man and took the religious name Michele. As a theologian, inquisitor and later cardinal, he became known for personal austerity and a strict commitment to Catholic doctrine. He was elected pope in 1566.
Implementing the decrees of the Council of Trent became one of his central tasks. Under his authority a new Roman Catechism, breviary and, in 1570, a revised Roman Missal were published. These works aimed to bring greater unity to Catholic teaching and worship. At the same time, Pius V took a hard line against Protestant movements and others he regarded as threats to religious unity.
His pontificate also became entwined with warfare. Pius V helped assemble the Holy League, whose fleet won a major victory over Ottoman forces at Lepanto in 1571. He died in Rome in 1572 and was canonised in 1712. His legacy reflects two closely connected aspects of the Counter-Reformation: the renewal of Catholic religious life and the vigorous enforcement of doctrinal boundaries.
