County of Edessa

State · 1099–1151 CE · at its largest around 1126 CE

First of the crusader states, founded by Baldwin of Boulogne in upper Mesopotamia; its capital fell to Zengi in 1144, prompting the Second Crusade.

On its lands while it lasted

• Edessa (302 BCE – 1150 CE): Capital of Kingdom of Osroene (63 BCE–214), County of Edessa (1099–1150).

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