Pope St. Pius V

Pope St. Pius V was born Antonio Ghislieri on 17 January 1504 at Bosco near Alessandria in Italy, of a poor family, and entered the Dominican order as a boy, becoming a friar of austere and holy life. Elected pope in 1566, he became the foremost agent of the Catholic Reformation, devoting himself with unbending zeal to carrying out the decrees of the Council of Trent and renewing the Church against the errors of the age.

He reformed the Roman Curia and the clergy, published the Roman Catechism, the reformed Breviary, and, in 1570, the Roman Missal that standardized the celebration of the Mass for four centuries. A man of deep prayer who kept his Dominican austerity even as pope, he organized the Holy League of Catholic states against the advancing Ottoman Turks, and when their fleet was decisively defeated at the naval battle of Lepanto on 7 October 1571, he attributed the victory to the intercession of Our Lady through the Rosary, instituting the feast now kept as Our Lady of the Rosary. He died in Rome on 1 May 1572 and was canonized in 1712.