Magister militum Ricimer defeats Emperor Avitus at Piacenza and becomes master of the Western Roman Empire.
Magister militum (Latin for "master of soldiers", plural magistri militum) was a top-level military command used in the later Roman Empire, dating from the reign of Constantine the Great. The term referred to the senior military officer (equivalent to a war theatre commander, the emperor remaining the supreme commander) of the empire. In Greek sources, the term is translated either as strategos or as stratelates.