Regnans in Excelsis ("Reigning on High") is a papal bull that Pope Pius V issued on 25 February 1570. It excommunicated Queen Elizabeth I of England, referring to her as "the pretended Queen of England and the servant of crime", declared her a heretic, and released her subjects from allegiance to her, even those who had "sworn oaths to her", and excommunicated any who obeyed her orders: "We charge and command all and singular the nobles, subjects, peoples and others afore said that they do not dare obey her orders, mandates and laws. Those who shall act to the contrary we include in the like sentence of excommunication." Among the queen's alleged offences, "She has removed the royal Council, composed of the nobility of England, and has filled it with obscure men, being heretics; oppressed the followers of the Catholic faith; instituted false preachers and ministers of impiety; abolished the sacrifice of the mass, prayers, fasts, choice of meats, celibacy, and Catholic ceremonies; and has ordered that books of manifestly heretical content be propounded to the whole realm and that impious rites and institutions after the rule of Calvin, entertained and observed by herself, be also observed by her subjects."The bull, written in Latin, is named from its incipit, the first three words of its text.



Pope Pius V (Italian: Pio V; 17 January 1504 – 1 May 1572), born Antonio Ghislieri (from 1518 called Michele Ghislieri, O.P.), was head of the Catholic Church and ruler of the Papal States from 8 January 1566 to his death in 1572. He is venerated as a saint of the Catholic Church. He is chiefly notable for his role in the Council of Trent, the Counter-Reformation, and the standardization of the Roman Rite within the Latin Church. Pius V declared Thomas Aquinas a Doctor of the Church.As a cardinal, Ghislieri gained a reputation for putting orthodoxy before personalities, prosecuting eight French bishops for heresy. He also stood firm against nepotism, rebuking his predecessor Pope Pius IV to his face when he wanted to make a 13-year-old member of his family a cardinal and subsidize a nephew from the papal treasury.By means of the papal bull of 1570, Regnans in Excelsis, Pius V excommunicated Elizabeth I of England for heresy and persecution of English Catholics during her reign. He also arranged the formation of the Holy League, an alliance of Catholic states to combat the advancement of the Ottoman Empire in Eastern Europe. Although outnumbered, the Holy League famously defeated the Ottomans at the Battle of Lepanto in 1571. Pius V attributed the victory to the intercession of the Blessed Virgin Mary and instituted the feast of Our Lady of Victory. Biographers report that as the Battle of Lepanto ended, Pius rose and went over to a window, where he stood gazing toward the East. "...[L]ooking at the sky, he cried out, 'A truce to business; our great task at present is to thank God for the victory which He has just given the Christian army'."