Pope Innocent III

Born Lotario dei Conti di Segni near Anagni and trained in theology at Paris and law at Bologna, Innocent III became pope at about 37 and raised the medieval papacy to the height of its power. He advanced a vision of papal authority over Christendom, intervening in imperial succession disputes and bringing kings, including John of England, to submission. He launched the Fourth Crusade, which notoriously sacked Christian Constantinople in 1204 against his stated wishes, and approved campaigns against the Cathars in southern France. He recognized the new mendicant movements of Francis and Dominic, and convened the Fourth Lateran Council (1215), whose far-reaching decrees, including on the Eucharist, confession, and restrictions on Jews, shaped Catholic life for centuries.