Why is the ninth month called September?
1620s, from Italian, literally "Frankish tongue." Originally a form of communication used in the Levant, a stripped-down Italian peppered with Spanish, French, Greek, Arabic, and Turkish words. The name is probably from the Arabic custom, dating back to the Crusades, of calling all Europeans Franks (see Frank). Sometimes in 17c. English sources also known as Bastard Spanish.