Battle of al-Qādisiyyah
The Parthian Empire occasionally used war elephants in their battles against the Roman Empire but elephants were of substantial importance in the army of the subsequent Sassanid Empire. The Sasanian war elephants are recorded in engagements against the Romans, such as during Julian's invasion of Persia. Other examples include the Battle of Vartanantz in 451 AD, at which the Sassanid elephants terrified the Armenians, and the Battle of al-Qādisiyyah of 636 AD, in which a unit of thirty-three elephants was used against the invading Arab Muslims, in which battle the war elephants proved to be "double-edged sword".