In hoc signo vinces

• In hoc signo vinces  meaning ‘In this sign you will conquer’.

 Constantine I

• Pronounced by Constantine I before he defeated Maxentius at the Battle of Milvian Bridge in 312 CE, after he had seen a Chi Rho sign in the sky. Eusebius, De Vita Imperatoris Constantini.

IHS

• Later, the letters became IHS, from the first three letters of ‘In Hoc Signo Vinces’ (In this sign you will conquer).
• These were Constantine I‘s famous words after seeing the Chi Rho letters in the sky before his victory over Maxentius at the Battle of Milvian Bridge in 312 CE.
• It also stands for the first three letters of the word ‘Jesus’ in Greek capital letters.