Roman army

Exercitus Romanus
Vexillum with the imperial aquila
Active	753 BC – 1453 AD
Country	Roman Kingdom Roman Republic Roman Empire Western Roman Empire Byzantine Empire
Size	28–50 legions
Headquarters	Aquincum Bonn Lauriacum Isca Augusta Alexandria Singara Regensburg Novae Busra
Motto(s)	'Gloria Exercitus'
Engagements	Roman–Gallic wars Samnite Wars Pyrrhic War Punic War Macedonian Wars Jugurthine War Mithridatic War Gallic Wars Roman civil wars Roman invasion of Britain Roman–Germanic wars Domitian's Dacian War Trajan's Dacian Wars Roman–Parthian War of 58–63 Jewish–Roman wars The Great Illyrian Revolt
Commanders
Commander-in-chief	Emperor (de facto; 27 BC–1453 AD) Consuls (de jure; 27 BC–1453 AD, 509 BC–27 BC) King (753 BC–509 BC)
Notable commanders	Marcus Furius Camillus Scipio Africanus Gaius Marius Julius Caesar Germanicus Flavius Stilicho Flavius Belisarius

The Roman army (Latin: exercitus Romanus) was the armed forces deployed by the Romans throughout the duration of Ancient Rome, from the Roman Kingdom (753 BC–509 BC) to the Roman Republic (509 BC–27 BC) and the Roman Empire (27 BC–476 AD), and its medieval continuation, the Eastern Roman Empire. It is thus a term that may span approximately 2,206 years (753 BC–1453 AD), during which the Roman armed forces underwent numerous permutations in size, composition, organisation, equipment and tactics, while conserving a core of lasting traditions.^[1][2][3]