Justinian's Wars · 533 – 554 AD
Justinian's wars were won by a small, superbly professional army built around one decisive weapon: the Byzantine mounted archer-lancer, who could shoot from a distance and charge home with the lance. Against the massed cavalry charges of the Goths and the Vandals, and behind the great walls of Rome and Ravenna, Belisarius and Narses used mobility, missile firepower, and siegecraft to defeat far larger forces — while command of the sea carried their armies from Africa to Italy to Spain.
The heart of Belisarius's army was the elite mounted soldier — armoured in mail, carrying both a powerful composite bow and a lance, and trained to do the work of both horse-archer and heavy lancer. These versatile cavalrymen, many of them the general's own retainers (bucellarii), could shower an enemy with arrows and then charge home, dominating the open battlefield.
Significance
This flexible archer-lancer was the war-winning weapon of the age, allowing tiny Byzantine armies to defeat much larger Vandal and Gothic hosts, and it defined Byzantine military superiority for centuries.
The powerful recurved composite bow, drawn from horseback, gave Byzantine cavalry a missile reach the Goths and Vandals could not match. Procopius specifically contrasted the Byzantine mounted archers with the Gothic horsemen, who relied on the lance alone, and credited the bow with winning battle after battle.
Significance
Byzantine mastery of horse-archery, learned in part from their Hunnic and steppe enemies and auxiliaries, was the single greatest tactical advantage of Justinian's armies over their Germanic opponents.
The Goths and Vandals were peoples of horsemen who favoured the shock charge with the lance, driving home in a mass to break the enemy line. Powerful and brave, this cavalry could be devastating — but it lacked missile weapons and discipline, and against Byzantine archery and prepared defences it was repeatedly shot down before it could close, most catastrophically at Taginae.
Significance
The Gothic charge was formidable but one-dimensional; its vulnerability to Byzantine horse-archery and combined-arms tactics was the tactical key to the whole war.
The bulk of the Gothic and other Germanic armies was foot soldiery armed with spear, shield, and sword, fighting in a dense shield-formation. Solid on the defensive, they lacked the archery and cavalry mobility of the Byzantines, and in the open they were often reduced to a passive mass while the cavalry decided the day.
Significance
The limitations of the Germanic infantry-and-lancer army against the balanced Byzantine force of horse-archers illustrated the military gap between the successor kingdoms and the surviving Roman empire.
The oared warship of the Byzantine navy, the dromon, and its accompanying transports gave the empire the command of the sea on which the whole reconquest depended — ferrying Belisarius's army to Africa, to Sicily, and up the Italian coast, and keeping it supplied. The Vandals had once been a great sea power, but their fleet was away when Belisarius struck.
Significance
Sea power was the strategic foundation of Justinian's wars, allowing the empire to project small armies across the Mediterranean and supply them where the Germanic kingdoms could not contest the water.
Byzantine foot soldiers carried the long sword (spatha), spear, and shield, and included both heavy infantry and foot archers. At Taginae and the Volturnus, Narses used dismounted heavy infantry to anchor his centre while his archers and cavalry did the killing on the flanks — a disciplined combined-arms role the Germanic armies could not replicate.
Significance
Well-drilled Byzantine infantry, used as a steady anchor for the army's missile and cavalry arms, was a key component of the combined-arms tactics that won the war's decisive battles.
The war turned on the great walled cities of the Mediterranean — Rome's mighty Aurelian Walls, the marsh-girt fortress of Ravenna, the defences of Naples and Carthage. Control of these strongholds was the object of most campaigning, and Belisarius's active defence of Rome behind its walls was the war's defining feat of fortification warfare.
Significance
The war was fought around fortresses more than in the open field, and the possession and defence of walled cities repeatedly decided its course — a foretaste of the siege-dominated warfare of the Middle Ages.
Taking a walled city meant siege machinery — battering rams, siege towers, and stone-throwing engines — as well as escalade, mining, and blockade. The Goths built great siege towers and rams to assault Belisarius in Rome, drawn by oxen, only to see them destroyed by his archers before they reached the walls.
Significance
The clash of Gothic siege engines against Byzantine active defence at Rome was one of the classic sieges of late antiquity, showcasing the technology and tactics of both assault and defence.
The armoured core of both armies wore mail hauberks, with Byzantine elite cavalry increasingly protected by lamellar (laced plates) and helmets, greaves, and shields. The heavy armour of the Byzantine archer-lancer let him fight at close quarters after emptying his quiver, combining protection with firepower.
Significance
The armour of the Byzantine cavalryman was integral to his dual role — protected enough to charge home with the lance, yet mobile enough to skirmish with the bow — the balance that made him so effective.
Belisarius's and Narses's armies were bolstered by contingents of Huns, Heruls, and other steppe and Germanic auxiliaries — superb light horse-archers and hard-fighting warriors whose skills complemented the regular cavalry. Their mobility and missile skill were repeatedly decisive in scouting, skirmishing, and the pursuit.
Significance
The recruitment of steppe horse-archers and foederati gave the Byzantine armies a mobility and missile capacity that magnified their small numbers, a hallmark of late-Roman and Byzantine military practice.
How the weapons and tactics of Justinian's Wars changed the nature of warfare.
Justinian's armies perfected the versatile heavy cavalryman who combined the composite bow with the lance — able to skirmish at range and then deliver a shock charge. Procopius singled out this dual capability as the decisive advantage over the lance-only cavalry of the Goths and Vandals.
Legacy
The archer-lancer became the signature Byzantine soldier for centuries, codified in later military manuals like the Strategikon, and represented the empire's fusion of Roman discipline with steppe horse-archery.
Belisarius's year-long defence of Rome turned siege warfare on its head: rather than passively enduring the blockade, he harried the huge Gothic army with constant sallies, ambushes, and archery, wearing it down until it broke — holding a great city with a fraction of the besiegers' numbers.
Legacy
Belisarius's aggressive, mobile defence of a fortress became a studied model of how a small, skilled garrison could defeat a far larger besieging army through initiative and firepower.
At Taginae and the Volturnus, Narses fielded a scientific combined-arms battle plan — a firm infantry centre with masses of archers on refused wings — that channelled the enemy's cavalry charge into a killing pocket and shot it to pieces. It was one of the finest tactical set-pieces of late antiquity.
Legacy
Narses's use of dismounted men-at-arms flanked by archers to defeat a cavalry charge anticipated, by eight centuries, the English longbow tactics of the Hundred Years' War, and remains a textbook example of combined arms.
The reconquest was made possible by Byzantine command of the sea, which let Justinian project small, elite armies across the entire Mediterranean — Africa, Sicily, Italy, Spain — and keep them supplied where the land-bound Germanic kingdoms could not respond.
Legacy
Justinian's wars demonstrated the strategic power of amphibious mobility for a maritime empire, a principle that underpinned Byzantine and later Mediterranean naval strategy for a millennium.
Justinian conquered kingdoms with astonishingly small forces — 15,000 men took Africa — relying on quality, professionalism, and elite retinues over mass. It was a deliberate strategy suited to an empire rich in money but short of manpower.
Legacy
The reliance on small, highly professional, cavalry-centred armies over large citizen levies became characteristic of Byzantine warfare and a model of achieving strategic results with limited but superior force.