County of Edessa

Also known as Comitatus Edessanus

The first and most exposed of the Crusader states — an inland Armenian–Frankish principality across the Euphrates that was also the first to fall.

The County of Edessa was the first of the Crusader states to be established. Baldwin of Boulogne, brother of Godfrey, broke off from the main First Crusade in early 1098 and made his way to the prosperous Armenian-Christian city of Edessa, where its ruler Thoros adopted him as heir. When Thoros was overthrown and killed in March 1098, Baldwin assumed control of the city as count, founding a state that stretched well east of the Euphrates and made common cause with the local Armenian population.

Edessa was geographically the most exposed of the Latin polities. Cut off from the sea, surrounded by Muslim Mosul and Aleppo to the south and east, and dependent on a thin Frankish military elite ruling a much larger non-Latin population, it was always vulnerable. Baldwin was succeeded in turn by Baldwin of Le Bourg (later Baldwin II of Jerusalem) and by the Courtenay line; the county lived in near-continuous warfare with the Artuqids and the Zengids.

The end came in late 1144, when Imad ad-Din Zengi of Mosul stormed the city while its count Joscelin II was absent. The fall of Edessa shocked Latin Christendom and was the immediate cause of the Second Crusade. The remaining western fragments of the county, governed from Turbessel, held out for another six years before they were sold to the Byzantines in 1150 — but most of those territories were quickly swept up by Nur ad-Din. Edessa was the first Crusader state created and the first to be lost.

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