English form of Latin Gregorius, which was from the Late Greek name Gregorios, derived from  gregoros meaning "watchful, alert". This name was popular among early Christians, being borne by a number of important saints including Saint Gregory Thaumaturgus (3rd century), Saint Gregory the Illuminator (4th century), Saint Gregory of Nyssa (4th century), Saint Gregory of Nazianzus (4th century), and Saint Gregory of Tours (6th century). It was also borne by the 6th-century pope Saint Gregory I the Great, a reformer and Doctor of the Church, as well as 15 subsequent popes.