Cor Tewdws

Cor Tewdws or Bangor Tewdws (Meaning "college" or "chief university" of Theodosius) was a Celtic monastery and college in what is now Llantwit Major, Glamorgan, Wales. It is believed to have been founded c. 395, making it the oldest established school in Great Britain. Today, the ruins of the monastery and college are believed to be under the St. Illtyd's Church in Llantwit Major.

The original college was said to have been established by (or in honor of) the Roman Emperor Theodosius I, and was named after him. In 380, Theodosius declared Nicene Christianity the only legitimate Imperial religion, ending support for traditional polytheistic religions and customs. The College of Theodosius is believed to have been founded c. 395, making it the earliest school, former or extant, in all of Great Britain. It has even been called "the oldest college in the world." It was founded during the last years of the Roman occupation of Britain, which ended c. 409 - 410 AD. After the withdrawal of the Roman legions, Britain suffered the incursion of the Irish, Scots, and Picts, who raided British settlements, sacking villages and carrying off the inhabitants as slaves. The college was reputedly burnt down in 446 A.D., with different sources attributing the destruction to Irish pirates and Saxon war bands. Later sources claim that St. Patrick was kidnapped by Irish pirates while at the College of Theodosius, but this claim is probably a later fabrication.

After the sack of the College of Theodosius, the site lay barren for 62 years, until it was re-established by St. Illtud c. 508 AD. According to the Book of Llandaff, St. Dubricius commissioned Illtud to re-establish the college, and the place came to be known as Llanilltud Fawr.

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