Gregor von Burtscheid (c. 940 - 4 November 999), also known as Gregor von Calabria or Gregory of Cassano, was the first abbot of the Burtscheid Abbey, founded on the order of Otto III, Emperor of the Holy Roman Empire.
Emperor Otto III founded the Burtscheid Abbey in 997 in the independent city of Burtscheid, and installed Gregor, who until this time was abbot of the Basilian monastery of St. Andreas in Calabria, as first Abbot.
Gregor died 4 November 999 with a reputation as a holy man, and thus after his death, his bones were held in the nearby Nicholas Chapel (Nikolaus-kapelle).
By the end of the 12th century, Gregor was bestowed the honor of the altars (zur Ehre der Altäre), and the date of his death was celebrated as a feast day at the abbey, until it was dissolved in 1802.
Since 2010, Abbot Gregor has been the patron saint of the dissolved rectories of St Gregorius, Sacred Heart, St. John, and St Michael, as well as the patron of the newly founded parish of St. Gregor von Burtscheid.