Byzantine army

The Byzantine army was the main military force of the Byzantine Empire, working together with the Byzantine navy. It grew from the Eastern Roman army and kept its strong discipline and smart strategies, much like the old Hellenistic armies. For many centuries during the Middle Ages, it was one of the best armies in western Eurasia.

Over time, the Byzantine army began to use more cavalry soldiers. It also included troops from many other places, such as the Huns, Cumans, Alans, and later the Turks, after the Battle of Manzikert. These groups served as skilled horse soldiers. The army relied on clever generals and also used foot soldiers from places like Frankish and Varangian lands.

From the 6th to the 12th centuries, the Byzantine army was very powerful. It defended the empire well and later went on to win back lost lands, especially under leaders like Nikephoros II Phokas, John Tzimiskes, and Basil II. The empire had a strong economy, which helped it gather large forces when needed.

Later, the Byzantine army changed again, using more professional soldiers and foreign troops. After losing parts of Asia Minor, the empire had trouble finding enough soldiers. By the time of the Fourth Crusade in 1204, the army was weaker, and the empire faced hard times. Even after that, leaders tried to rebuild the army, but civil wars and new threats, like the rising Ottoman Empire, made it very difficult.

History

After the Muslim conquests, the Byzantine army moved its forces to Asia Minor and started a new system called the thematic system. Even with these big changes, the army kept its organization and tactics from the 6th to the 11th centuries. Events like the Battle of Manzikert in 1071, Seljuk invasions, the Crusades, and Norman attacks made the Byzantine state weaker and its military weaker, so they had to rely more on foreign soldiers.

The army under Diocletian and Constantine

The Eastern Empire began when Emperor Diocletian created the Tetrarchy in 293. He changed the army from large foot soldier groups to smaller border and field armies. Cavalry became more important, but foot soldiers were still the main part of the army. The army prepared for campaigns with thousands of foot soldiers and mounted archers.

Emperor Constantine I

The army of Justinian I and his successors

Justinian I’s army was formed to face growing threats, especially from Persia. The old Roman legions and groups were replaced with smaller Greek battalions and horse regiments. There were different types of troops, including guard troops, field armies, border guards, allied groups, and private soldiers of generals. The army’s size varied.

Middle Byzantine period, 7th–11th centuries

The Themata

A 10th–12th century ivory relief of Byzantine swordsmen – Berlin Bode museum.

The themata were areas where generals had both military and civilian power. They started after big losses of land to Muslim conquests. The first themata were in Asia Minor and came from old field armies. Soldiers were given land to support themselves and their families.

The Imperial tagmata

The tagmata were professional armies formed by Emperor Constantine V. They were based in or near Constantinople and included heavy cavalry and infantry. The main tagmata were the Scholai, Exkoubitoi, Arithmos or Vigla, and Hikanatoi.

The army during the Komnenian dynasty

Emperor John II Komnenos became renowned for his superb generalship and conducted many successful sieges. Under his leadership, the Byzantine army reconquered substantial territories from the Turks.

Establishment and successes

In 1081, the Byzantine Empire was small and weak. Emperors Alexios I Komnenos, John II Komnenos, and Manuel I Komnenos built a new, strong army. This Komnenian army included guards like the Varangian Guard and levies from provinces. It was effective and could campaign in many places, but it needed strong leaders to work well.

Neglect under the Angeloi

After Andronikos I Komnenos died in 1185, the Angeloi took over. They did not care for the military and let the army weaken. Enemies like the Turks, Serbs, and Hungarians took advantage of this weakness.

A map of the Byzantine Empire under Manuel Komnenos, c. 1180.

Analysis of the Byzantine military collapse

Structural weaknesses

The theme system, which had helped the empire succeed, broke down. Without it, the army became more expensive and needed strong leaders. After Manuel I Komnenos died in 1180, the Angeloi’s poor leadership made the army weak. By 1204, the Fourth Crusade sacked Constantinople.

Armies of the successor states and of the Palaeologi

After 1204, the Byzantine Empire was smaller and poorer. The army had fewer soldiers and relied more on foreign mercenaries. By 1453, when Constantinople fell, the Byzantine army had fewer men, against many Ottoman troops. The emperor Constantine XI led the last defense before the city fell.

Name	No. of personnel	No. of subordinate units	Officer in command
Thema	9 600	4 Tourmai	Strategos
Tourma	2 400	6 Droungoi	Tourmarches
Droungos	400	2 Banda	Droungarios
Bandon	200	2 Kentarchiai	Komes
Kentarchia	100	10 Kontoubernia	Kentarches/Hekatontarches
	50	5 Kontoubernia	Pentekontarches
Kontoubernion	10	1 "Vanguard" + 1 "Rear Guard"	Dekarchos
"Vanguard"	5	n/a	Pentarches
"Rear Guard"	4	n/a	Tetrarches

Byzantine troop types

Main article: Byzantine battle tactics

Cataphracts

The Byzantines had heavy cavalry called "cataphracts" to match strong enemy cavalry. These soldiers and their horses wore thick armor. They carried long spears, bows, and heavy clubs. Though they moved slowly, they were very powerful in battle, especially under Emperor Nikephoros II. Some of these troops were even heavier armored and were called clibanarii.

Cavalry

The Byzantine cavalry were very good at fighting on the wide plains of Anatolia and northern Syria. They used long spears, heavy clubs, swords, and strong curved bows. This helped them defeat faster enemies like the Arabs, Turks, Hungarians, and Pechenegs.

The deployment of the armies in the Battle of Dara (530), in which Byzantium employed various foreign mercenary soldiers, including the Huns.

By around 900–1200, the regular cavalry were divided into three types: heavily armored soldiers for strong attacks, medium-weight soldiers with mail or scale armor, and lightly armed horse archers.

Infantry

The Byzantine armies always included professional infantry soldiers, continuing traditions from older Roman times. However, during the middle period, cavalry became more important. Infantry soldiers carried long spears, swords, or axes, and used lead-weighted darts called plumbata. They also had large shields, helmets or felt caps, and thick quilted or leather armor. Richer soldiers might have iron lamellar or chain mail, but most infantry were not as heavily armored as earlier soldiers. Their strength came from their strong organization and discipline.

Pronoiars

Pronoiar soldiers appeared in the twelfth century, especially under Emperor Manuel I Komnenos (1143–1180). These soldiers were given land to live on instead of money. They collected taxes from people living on their land and kept some of the money. They were similar to knights in western countries but still owed loyalty to the emperor, who owned the land. These soldiers were usually cavalry and had mail armor, lances, and protective clothing for their horses. After 1204, many of these troops served in the Empire of Nicaea in western Asia Minor.

Akrites

Akrites were soldiers who protected the borders of the Byzantine Empire in Anatolia. They appeared after Arab attacks in the 7th century and became important during the 8th to 11th centuries. These soldiers were native Greeks from areas like Cappadocia and Pontus. They were given land in exchange for defending the borders. Each akritas could hire and train small groups of local soldiers. They were good at defending against attacks, especially from Arab horsemen. They used typical Byzantine weapons and armor of their time, such as shields, thick wool or mail armor, spears, swords, clubs, axes, bows, and javelins. Their tactics focused on quick attacks and ambushes.

Foreign and mercenary soldiers

The Byzantine army used soldiers from many different places. These foreign troops helped the regular army and sometimes made up most of the army. They showed the wealth and strength of the Byzantine Empire.

During the Byzantine time, foreign troops were called different names. In the late Roman period, they were called foederati ("allies") in Latin, and later Phoideratoi in Greek. They were also known as the Hetairoi ("Companionships") and often served in the Imperial Guard. This guard was split into three groups, each led by a Hetaireiarches – "Companionship lords".

Barbarian tribes

In the 6th century, the Byzantine army recruited soldiers from several barbarian tribes. These included the Heruli, the Huns, and the Gepids, who lived north of the Danube River.

Coin of emperor Basil II, founder of the Varangian Guard.

These barbarian mercenaries helped Emperor Justinian reclaim lost lands. The Byzantine general Belisarius used Hunnic archers and Heruli mercenaries. Later, he used Heruli infantry and Hunnic horsemen.

In 552, the general Narses defeated the Ostrogoths with an army that included many Germanic soldiers. Two years later, Narses defeated a mixed army of Franks and Alemanni.

During the Komnenian period, mercenary units were often named after their homeland. Some of these units, like the Skythikoi, also acted as police in Constantinople.

Varangian guard

The most famous unit in the Byzantine army was the Varangian Guard. It began with Rus sent to Emperor Basil II by Vladimir of Kiev in 988. These soldiers became an elite group and the emperor's personal bodyguard. Their commander was called the Akolouthos.

At first, the Varangians were mostly from Scandinavia, but later they included many Anglo-Saxons. The Varangian Guard fought well at the Battle of Beroia and were at the Battle of Sirmium, where the Byzantine army defeated the Kingdom of Hungary.

Byzantine weapons

Handheld weapons

Byzantine fresco of Joshua from the Hosios Loukas monastery, 12th to 13th century. A good view of the construction of the lamellar klivanion cuirass. Unusually, the Biblical figure is shown wearing headgear; the helmet and its attached neck and throat defences appear to be cloth-covered. Joshua is shown wearing a straight spathion sword.

The Byzantines used weapons from their Roman past, such as swords, lances, and javelins. As time passed, they added new weapons. They had many kinds of swords, both straight and curved, for soldiers on foot and on horseback.

They also used long spears and lances, and light throws for attacks from far away. Maces and axes were used to break through enemy armor. Bows and arrows were common for archers, and they had special tubes to shoot many small darts quickly.

Shields

Byzantine soldiers used different kinds of shields. Early shields were large and round, but later they used smaller round shields and longer, kite-shaped shields. Some shields had patterns or writings on them, and later some even had pictures like lions.

A Byzantine fresco of Saint Mercurius with a sword and helmet, dated 1295, from Ohrid, North Macedonia

Armor

Byzantine soldiers wore armor to stay safe. Early armor included special layered armor called lamellar. They also used chainmail, which looked like tiny linked rings. Helmets came in many styles, including ones made from layers of material and others made from metal pieces.

Artillery

The Byzantines used big throwing machines called trebuchets. These could throw heavy weights to attack enemy walls. They also used special tubes to shoot a very hot, sticky liquid called Greek Fire from their ships and walls.

Byzantine military doctrine

Further information: Byzantine battle tactics

The Byzantine army was different from the Roman legions. Its main strength came from heavily armed cavalry called Cataphracts, which developed from the Clibanarii in earlier times. Foot soldiers were still used, but they mostly helped the cavalry.

Leaders of the Byzantine army cared about the soldiers' spirit before battles. They believed their role as a Christian empire was important. Before fighting, they would prepare in special religious ways, like showing crosses and holy items. This helped the soldiers feel brave and focused.

Major battles of the Byzantine Empire

Early Byzantine period

Some important battles from the early years of the Byzantine Empire include:

Middle Byzantine period

Important battles from the middle years include:

Late Byzantine period

Some of the last major battles include: