The School of Edessa (Syriac: ܐܣܟܘܠܐ ܕܐܘܪܗܝ), often confused with the School of Nisibis, was a theological school of great importance to the Syriac-speaking Assyrian world. It had been founded as long ago as the 2nd century by the kings of the Abgar dynasty. In 363, Nisibis fell to the Persians, causing St. Ephrem the Syrian, accompanied by a number of teachers, to leave the School of Nisibis. They went to Edessa, where Ephrem took over the directorship of its school. Then, its importance grew still further. There were innumerable monasteries at Edessa housing many monks and offering many cells for their abode. Ephrem occupied a cell there, practicing the ascetic life, interpreting Holy Scripture, composing poetry and hymns and teaching in the school, as well as instructing young girls in church music.
In 489, after the Nestorian Schism, the Byzantine emperor, Zeno, ordered the school summarily closed for its teachings of Nestorian doctrine. Its scholars moved back to the School of Nisibis.
The first recorded director of the School of Edessa was Qiiore. In the early 5th century had ascetic and scholarly qualifications and had administrative ability. Occupying the Chair of Exegesis (mepasqana), he replaced the texts of Ephraim with those of Theodore of Mopsuestia. With that seminal decision, Qiiore embarked upon a course of study that was to mix the deductive principles of Aristotle with Theodore's Dyophysite creed.