Legio IX Hispana

Legio IX Hispana
Map of the Roman empire in AD 125, under emperor Hadrian, showing the IX Hispana's last attested location at Noviomagus Batavorum on the Rhine (Nijmegen, Netherlands)
Active	Before 58 BC to sometime in the AD 2nd century
Country	Roman Republic and Roman Empire
Type	Roman legion (Marian)
Role	Infantry assault
Size	c. 5,400
Garrison/HQ	Hispania Tarraconensis 41–c. 13 BC ? Pannonia AD 9–43 Eboracum (Britannia) 71–c. 121 ? Noviomagus (Germania Inferior) c. 121–130
Nickname(s)	The Lost Legion
Mascot(s)	Bull
Engagements	Gallic Wars (58–51 BC) Cantabrian Wars (29–19 BC) Roman conquest of Britain Boudican revolt Battle of Mons Graupius
Commanders
Notable commanders	Julius Caesar Quintus Petillius Cerialis Gnaeus Julius Agricola

Legio IX Hispana ("9th Spanish Legion"),^[1] also written as Legio VIIII Hispana,^[2] was a legion of the Imperial Roman army that existed from the 1st century BC until at least AD 120. The legion fought in various provinces of the late Roman Republic and early Roman Empire. The nickname "Hispana" was gained when it was stationed in Hispania under Augustus. It was stationed in Britain following the Roman invasion in AD 43. The legion disappears from surviving Roman records after c. AD 120 and there is no extant account of what happened to it.^[4]

The unknown fate of the legion has been the subject of considerable research and speculation. One theory (per historian Theodor Mommsen) was that the legion was wiped out in action in northern Britain soon after AD 108, the date of the latest datable inscription of the Ninth found in Britain, perhaps during a rising of northern tribes against Roman rule. This view was popularised by the 1954 novel The Eagle of the Ninth in which the legion is said to have marched into Caledonia (modern-day Scotland), after which it was "never heard of again".

This theory fell out of favour among modern scholars as successive inscriptions of IX Hispana were found in the site of the legionary base at Nijmegen (Netherlands), suggesting the Ninth may have been based there from c. AD 120, later than the legion's supposed annihilation in Britain.^{[4]: ch. 11} The Nijmegen evidence has led to suggestions that IX Hispana was destroyed in later conflicts of the 2nd century. Suggestions include the Bar Kokhba revolt (AD 132–135) or Marcus Aurelius's war against Parthia (AD 161–166) in Armenia.^{[4]: ch. 12} However, some scholars^[5] have ascribed the Nijmegen evidence to a mere detachment of IX Hispana, not the whole legion.

In any event, it is clear that the IX Hispana did not exist during the reign of the emperor Septimius Severus (r. AD 193–211), as it is not included in two identical but independent lists of the 33 legions existing in this period.