It is possible that the origins of the Ninth Legion may go back to Caesar's IX, which was already in Gaul when he assumed governorship of the Province in 58bce, but direct descent is not backed-up by any epigraphic or literary references.
Caesar's IX was disbanded c.46 or 45bce, and some veterans settled in Picenum, others perhaps at Histria. Caesar's IX was reformed by Ventidius Bassus c.44bce, but were soon disbanded once more. The legion was possibly re-formed by Octavian c.41 to 40bce and served with him until Actium in 30bce after which they were posted to Spain.
The legion was active in Hispana province from 30 to c.19bce, and gained distinction during the campaigns of Augustus c.24.
The legion was transferred to the Rhenus frontier c.20bce, but little is known of the legion's Germanic posting, apart from the tombstone of a Colonist at Cales in 14bce.
The legion was posted to Pannonia ad9 and was permanently stationed there until ad43, apart from a short stint in Africa. The legion was given to Junius Blaesus in ad20 to help counter the rising of Tacfarinas in Mauretania and Africa (between ad17 to 24), but returned to Pannonia before the revolt was concluded.
Soon after the move to Germany, Legio IX acquired its permanent title Hispaniensis, meaning 'stationed in Spain'. Later the form Hispana ('Spanish') was preferred. The title was in use by the middle of Augustus' reign (attested by ILS2321). Another of the legion's titles, Macedonica, was awarded after service in the Balkans sometime during the early Julio-Claudian era. (Vide Legio II Augusta)
The Ninth Legion saw active service during the Claudian Invasion of Britain under Aulus Plautius in ad43 and was thereafter divided between Vexillation Fortresses at Longthorpe near Peterborough in Cambridgeshire and at Newton-on-Trent in Lincolnshire before their legionary fortress was built c.ad65 at Lindum (Lincoln, Lincolnshire).
During the early stages of the Boudiccan Revolt of ad60/61 the legionary legate Quintus Petillius Cerialis, tried to use IX Hispana to prevent the sack of Londinium, however, the legion was badly mauled and was forced to retire to its campaign fortress at Longthorpe. The Ninth later had its complement made good with a contingent of two thousand men taken from the legions stationed on the Rhine (Tacitus, Annals, XIV:38).
The Legion moved from its fortress at Lincoln to a campaign fortress at Malton in North Yorkshire in ad71, and were replaced at Lincoln by Legio II Adiutrix. The proconsular governor Q. Petillius Cerialis then took personal command of his old legion, and together with Legio XX Valeria Victrix commanded by the legate Gnaeus Julius Agricola, moved against the forces of Venutius of the Brigantes. Legio IX Hispana comprised the main force and moved along the vale of York, while XX Valeria moved up the western side of the Pennines in a pincer movement, crushing the forces of Venutius in a pitched battle at Stanwick.
The campaigns of emperor Domitian in ad83 against the Chatti in the Taunus region of the Middle Rhine called for vexillations from all four British legions (i.e. II Augusta, II Adiutrix, XX Valeria and, of course, the Ninth). The senior tribune of Legio IX Hispana was decorated during this campaign (I.L.S., 1025).
It is possible that a vexillation of the Ninth were sent to the lower Rhine during the second Dacian War c.ad86 when Legio II Adiutrix was removed from Britain and Legio VI Victrix, then based at Vetera on the Rhine was reduced in strength and a vexillation of this legion moved to the east.
Following the removal of Legio X Gemina from Noviomagus (Nijmegen, Netherlands) in Batavia in ad104, a considerable amount of reconstruction was undertaken at the Nijmegen fortress by a vexillatio Britannica, it is possible that a detachment of the Ninth Spanish Legion were responsible for this work.
The last known testament of the Ninth Legion's activities in Britain are legionary stamps associated with the rebuilding in stone of the legionary fortress at Eburacum in ad108. The Ninth Legion disappeared from York c.ad120, and were replaced by Legio VI Victrix, brought from Germany by Aulus Platorius Nepos c.ad122, and stationed in the newly-rebuilt fortress.
The presence of Legio IX Hispana is attested at Nijmegen though not dated (vide supra). It is possible that they were stationed here for a few years after leaving Britain c.ad120 before being posted to the East.
An alternative suggestion is that the Ninth Legion were set to work with the other three British legions on Hadrian�s Wall for a time after ad122, but the section they were allocated was the turf wall to the west, and thus left behind no inscribed masonry attesting their presence.
Another suggestion, also tentative, is that the Ninth Legion acted with great cowardice during an attack from the tribes of the Caledonian Lowlands c.ad125, and that the soldiers so disgraced themselves that the legion was disbanded and the mention of its name - and therefore the recording of its fate - was forbidden.
Then again, Legio IX Hispana was perhaps annihilated in Judaea under Hadrian, ad132 to 135, or later under Marcus Aurelius, in Armenia, ad161. No longer thought to have been destroyed in Britain, but to have been transferred, first to Germany, and then to the East. (see Dio lxxxi.2 on a disaster ad161).
It has also been suggested that Legio IX Hispana may have been lost in Cappadocian campaigns of ad161 or on the Danube during the ad162 revolt of the Chatti.
Roman historians were extremely reticent in recording the fate of legions which had been disgraced, and the recording of their fate may have been constitutionally banned. Similarly, those legions which were annihilated in battle were not generally made known for reasons of continuing public morale and perhaps, to ensure political stability.
An inscription found in Rome (I.L.S. 2288) and dated to the reign of Marcus Aurelius (ad161-ad180) lists twenty eight legions in west-east order, with IX Hispana and XXII Deiotariana missing, the latter legion had been part of the Garrison of Egypt since c.25bce, and were possibly destroyed or disbanded under Hadrian in Judaea c.ad132-135.
The tombstone of Titus Flavius Virilis, found at Lambaesis in North Africa, adds further to the mystery. He apparently held the centurionate in six legions, his last post being Hastatus Posterior Legio IX, he died in service whilst training recruits aged about 65. Since his last posting was with the Ninth Legion and he died in service, this must surely mean that at least part of the legion was stationed for some time in Africa.