The Pope led an army into battle and lost. Leo IX personally marched against the Normans in southern Italy, convinced God would deliver victory. He was wrong. Humphrey of Hauteville's 3,000 Norman cavalry shredded the papal forces at Civitate in June 1053, then captured the Pope himself. Leo spent nine months as a Norman prisoner. And here's the reframe: that humiliation helped shatter the relationship between Rome and Constantinople, accelerating the Great Schism of 1054. The Pope's military gamble didn't just fail. It helped split Christianity in two.
June 18, 1053
973 years ago
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