The Goths here mentioned are the Gothi minores dwelling on the north of the Danube, where Ulfilas, “the Apostle of the Goths” (311–381), converted many of his countrymen to Christianity.  After suffering severe persecution, he was allowed by the Constantius to take refuge with his Arian converts in Mœsia and Thrace.  This migration took place in 348 a.d., the same year in which Cyril’s Lectures were delivered.