Why is the ninth month called September?
Cestre (1086), from Old English Legacæstir (735) "City of the Legions," from Old English ceaster "Roman town or city," from Latin castrum "fortified place" (see castle (n.)). It was the base of the Second Legion Adiutrix in the 70s C.E. and later the 20th Legion Valeria Victrix. But the town's name in Roman times was Deoua (c.150 C.E.), from its situation on the River Dee, a Celtic river name meaning "the goddess, the holy one."