Late Middle Ages (15th century)
Feast: October 23
A lawyer who became a Franciscan after a vision in prison, preached across Europe, and rallied a peasant army that broke the Ottoman siege of Belgrade.
John of Capistrano was governor of Perugia and a married man when a political dispute landed him in prison. During captivity, he had a vision — or a breakdown, depending on who tells the story — that changed everything. He annulled his unconsummated marriage, joined the Franciscans, and studied under Bernardine of Siena. He became a preacher, an inquisitor, and a diplomat, spending decades crisscrossing Europe on missions for the pope. His legacy is complicated. As an inquisitor, he was harsh, and his actions against Jewish communities in central Europe were cruel even by the standards of his time. But when the Ottoman Empire besieged Belgrade in 1456, John was seventy years old and he rallied a volunteer army of Hungarian and German peasants, preaching to them until they agreed to fight. On July 22, the defenders broke the siege — one of the decisive battles of the fifteenth century, which halted the Ottoman advance into central Europe for decades. John himself reportedly led charges, carrying a crucifix instead of a sword. He died of plague three months later, in October 1456, in the camp outside Belgrade. History remembers his courage and his cruelty together.