Possible Clues:

• Year in the reign of England's King Stephen
• XXIII x L
• CCXXX x V
• CXV times X
• Year in which Middle English began, by tradition
• 1150, to Cato
• 1,150, to Brutus
• Livy's 1,150
• 12th-century date
• Cato's 1,150