Fall of Edessa
Zengi of Mosul took Edessa, destroying the first crusader state; the news prompted the Second Crusade.
In the autumn of 1144, while Count Joscelin II of Edessa was away with his army, Zengi, ruler of Mosul and Aleppo, besieged the city. After nearly four weeks of mining under the walls he took it on 24 December, killing or capturing the Franks but sparing the Armenian and Syriac Christian inhabitants.
Zengi became a hero of holy war in the Islamic world. After his death in 1146 his son Nur ad-Din carried on the counter-offensive, and the rest of the county was gone by about 1150. On hearing the news Pope Eugenius III called for a new crusade.