The School of Nisibis (Syriac: ܐܣܟܘܠܐ ܕܢܨܝܒܝܢ), for a time absorbed into the School of Edessa, was an educational establishment in Nisibis (now Nusaybin, Turkey). It was an important spiritual centre of the early Church of the East, and like the Academy of Gondishapur, it is sometimes referred to as the world's first university. The school had three primary departments teaching: theology, philosophy and medicine. Its most famous teacher was Narsai, formerly head of the School of Edessa.
The school was founded in 350 in Nisibis. In 363, when Nisibis fell to the Persians, St. Ephrem the Syrian, accompanied by a number of teachers, left the school. They went to the School of Edessa, where Ephrem took over the directorship of the school there. It had been founded as long ago as the 2nd century by the kings of the Abgar dynasty. When Ephrem took over the school, its importance grew still further. After the Nestorian Schism, when the Byzantine emperor Zeno ordered the school closed for its teachings of Nestorian doctrine, deemed heretical by Chalcedonian Christianity, the School moved back to Nisibis.
The school was founded around 350 by Jacob of Nisibis (Mar Yaqub). It model was the school of Diodorus of Tarsus in Antioch. It was an ideal location for a Syriac school: in the centre of the Syriac-speaking Assyrian world but still in the Roman Empire, which had just embraced Christianity. Most of Mesopotamia was under Sassanid Persian rule, which was still trying to revive the ancient Zoroastrian religion.