Saint and Martyr Antipope Felix II, (†365) was a Roman archdeacon in the 4th century who was installed irregularly in 355 as an antipope and reigned until 365 after Emperor Constantius banished the current pope, Liberius. Constantius, following the refusal of the laity to accept Felix, attempted to have them co-rule, but Felix was forced to retire. He was resented in his lifetime but has enjoyed a more popular memory since. Antipope, in the Roman Catholic church, is any figure attempting to oppose the legitimately elected Bishop of Rome, with Felix being among the unsuccessful.
Saint Pope Leo IX (†1054), venerated as a saint in the Catholic Church, is considered to be one of the most historically significant popes of the Middle Ages; he was instrumental in the precipitation of the Great Schism of 1054, considered the turning point in which the Catholic and Eastern Orthodox Churches formally separated. Leo IX favored traditional morality in his reformation of the Catholic Church. His feast day is celebrated on 19 April.
Saint Liborius of Le Mans (†397) was the second Bishop of Le Mans. He is the patron saint of the cathedral and archdiocese of Paderborn in Germany, invoked against calculi; against colic; against fever; and against gallstones. His feast day is commemorated on July 23.