Edessa, the capital of Abgar’s dominions, was a city of Northern Mesopotamia, near the river Euphrates. History knows nothing of the city before the time of the Seleucidæ, though tradition puts its origin back into distant antiquity, and some even identify it with Abraham’s original home, Ur of the Chaldees. In the history of the Christian Church it played an important part as a centre of Syrian learning. Ephraem, the Syrian, founded a seminary there in the fourth century, which after his death fell into the hands of the Arians.