One of the world’s most important medieval castles, Krak des Chevaliers, was conquered by Sultan Baibars.
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German mathematician Carl Friedrich Gauss became the first person to prove quadratic reciprocity law.
The first person in the world to be diagnosed with Alzheimer's died.
The first idea of a fire escape was patented.
The iconic historical Winchester Cathedral in Hampshire, England, was dedicated to Bishop Walkelin.
Roman Emperor Caracalla was stabbed to death by a guard while urinating.
