April 15, 1638: The castle of Hara, located on the Shimabara Peninsula, Japan, falls to invaders. Masuda Shiro Tokisada defended the fortress with 37,000 Christians, 17,000 of them combatants. They fought valiantly to the end-even the women and children. After the battle, all of the survivors were subsequently beheaded, save one Judas (Yamada) who had plotted to open the castle gate to the enemy.

April 15, 1889: Belgian Roman Catholic priest Joseph Damien, a missionary to lepers on Molokai, Hawaii, dies from the disease.

April 15, 1892: Dutch devotional writer Corrie ten Boom, known for hiding Jewish refugees in her home during World War II (an act dramatized in the 1971 film The Hiding Place) is born. She also died on this date in 1983.

April 16, 1879: Bernadette Soubirous, who at age 14 became famous for her visions of the Virgin Mary at Lourdes, dies in Nevers, France. In 1933 the Roman Catholic church declaired her a saint.

April 18, 1161: Theobald, Archbishop of Canterbury, dies. He repeatedly quarreled with his superiors about church appointments and other political questions, but he the influential French abbot Bernard of Clairvaux supported him. Theobald helped strengthen the English church and build the career of Thomas Becket, whom he recommended as chancellor to England's newly crowned King Henry.

April 18, 1587: English Protestant historian John Foxe, author of Actes and Monuments of Matters Happenning to the Church (the shorter version is now known as Foxe's Book of Martyrs), dies at age 71.

April 19, 526: Justinian I is crowned Roman Emperor in Constantinople's magnificent cathedral, the Santa Sophia. Attempting to restore political and religious unity in the eastern and western empires, he ruthlessly attacked pagans and heretics and created the Code of Justinian, a massive restructuring of law (including much regarding the relationship of church and state) that would be the basis of legislation for nearly a millennium.)

April 19, 1054: Pope Leo IX dies. Because Leo refused the title of Ecumenical Patriarch to Michael Cerularius (Patriarch of Constantinople) and demanded recognition of the filioque clause (the western addition to the Nicene creed that asserts "the Holy Ghost . . . proceeds from the Father and the Son), he is usually assigned responsibility for the final break between Eastern and Western Christianity, though the conventional date for the schism is July 16.

April 21, 1109: Anselm, archbishop of Canterbury and one of the most profound thinkers of the Middle Ages, dies around age 76. He attained fame for his argument that faith is the precondition of knowledge ("credo ut intelligam"), his "satisfaction theory" of the atonement ("No one but one who is God-man can make the satisfaction by which man is saved") and for his ontological argument for God's existence.

April 21, 1142: Medieval French philosopher, teacher, and theologian Pierre Abelard dies. Though well-known for his writings on revelation and the relationship between faith and knowledge, he is probably most remembered for his love letters to Heloise, a nun.

April 21, 1897: A.W. Tozer, devotional writer (The Pursuit of God and The Knowledge of the Holy) and influential pastor in the Missionary Alliance Church, is born.