Mongols Capture Baghdad Ending Abbasid Caliphate
In the early thirteenth century, the Mongol Empire under Hulegu Khan expanded westward after securing Persia and defeating the Nizari Ismailis. The Abbasid Caliph al-Musta'sim in Baghdad had refused to submit or provide support, prompting a Mongol invasion of Mesopotamia. Mongol forces besieged the city starting in late January 1258, breaching defenses with siege engines by early February. On February 10, the caliph surrendered personally to Hulegu, leading to the city's sack shortly afterward. The fall resulted in massive casualties and the destruction of libraries and infrastructure, marking the effective end of the Abbasid Caliphate as a political entity.