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The papal bull wasn't even valid—Pope Leo IX had died three months earlier. But
1054 Event

July 16

Great Schism: Eastern and Western Christianity Split Forever

The papal bull wasn't even valid—Pope Leo IX had died three months earlier. But Cardinal Humbert didn't know that when he marched into Hagia Sophia on July 16, 1054, interrupting Saturday liturgy to slam his excommunication decree onto the altar. Patriarch Michael Cerularius was dining nearby. He rushed back, read the Latin insults accusing Greeks of heresy, and issued his own excommunication five days later. The split was supposed to be temporary. Nine centuries later, a billion Christians still worship in separate churches because three men couldn't wait to confirm their boss was alive.

July 16, 1054

972 years ago

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What Else Happened on July 16

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