The Byzantine Empire was the eastern part of the united Roman Empire which lasted until the Ottoman conquest in 1453. The Byzantine Empire was not a separate entity from the Roman empire but served as a persistent remnant of the larger structure, which survived 1,000 years after its western half collapse. Despite this indisputable heritage, there were differences between Rome under Augustus, Marcus Aurelius, and Honorius and the Byzantine empire under Justinian, Basil, and Nikephoros. One of the main ways in which the Byzantine broke from their predecessors was in military doctrine. Byzantine army adapted to fit the methods of the age in which it existed, becoming one of the greatest armies in the medieval world.
Army Tactical Changes
In the 4th century AD, the cavalry in the Byzantine army had a secondary role as it was employed as scouts or deployed to the rear or flanks. The army was predominately composed of infantry. The calvary tactics were influenced by the barbarian mercenaries, especially the nomadic horse lords Huns, who used their exotic mounting skills to gain employment in the Byzantine army. The calvary used the heavy-mounted bowman wielded a standard symmetrical composite bow as his primary weapon replacing the spear and javelin armed horseman of earlier days.. This standard model was easy to manufacture in large quantities; thus, equipping the troops would be easier. For protection, the ideal trooper donned armor, including a mail corselet and greaves but did not wear a helmet so that his accuracy was not significantly impaired. The horse archers (Hippo-Toxotai) did not clad their mounts in armor. They used the empire’s terrain-specific resources as they reared the notably powerful Cappadocian steads, bred in military stables for this specific purpose. The Cappadocian stead could easily maintain high speed even though armored men were atop them. Different types of mounted troops supplemented the armored cavalry archers, depending on the situation. Most of these horse warriors were mercenary foederati brought into the empire from outside. The Byzantine foederati were mostly unassimilated barbarians armed in their native styles but fighting under Byzantine command.
The Byzantine empire also maintained the quality of the infantry troops, which were not as polished as the standardized soldiers of the Roman empire. The proto-state infantry was equipped with a spear and a bow as standard equipment and supplemented by a sword as a sidearm.. The Toxotai (archers) relied on a small shield to protect his face from enemy attacks. There was also change in the training and tactics of the Byzantine army, such as in the practice of archery, both mounted and on foot. The Byzantine army modus operandi depended on accuracy, precision, and stopping power. The Byzantine infantry implemented the Chiliarchiai formation, which comprised 1,000 men entailing 650 skutatoi and 350 toxotai. In formation, the skutatoi represented the first three lines, while the remaining were the toxotai. The infantry was deployed directly facing the enemy.
During battles, the proto-state infantrymen gathered into a phalanx, compact but not overly cramped space. They raised their shields, thrust forward their spears holding ground, and pushed on in a wedge formation to break the enemy lines and repulse a cavalry charge. The infantrymen’s training was so sophisticated in proper interval maintenance that none of the spearmen interfered with any of their comrades. At the enemy’s approach, the prostate infantry would lose their primary weapon into the ground, losing bow fire into the enemy until their progress began to slow. At this point, the spear would be taken up once again. Such a form of relatively short weaponed spearmen provided an excellent middle ground between the flexibility of the gladius welding Maniples and the rigidity and range of an old Sarissa phalanx. The light cavalry was used for scouting, while the heavily armored cavalry was used to flank and envelop the enemy. The calvary either held or advanced to outflank the weakened enemy depending on the might of the foe. The front-line archers were used to weaken the enemy allowing the cavalry to charge, dismantling their formations.
The Byzantine Empire was constantly raided by the Bulgarian empire, the Slavs from the west, and the Arabs from the east. The raids, coupled with the grain supply being cut off from annexed Egypt, caused widespread famine, depopulation, and immigration. The new system that emerged organized the Byzantine empire into themes (themata) from 650 to 750 AD. The theme was a largely autonomous military organization led by Strategoi. Each soldier within a theme unit was tied to a food-producing land. Themes represented a system of semi feudalism where the peasant farmers of the land were obliged to train a soldier.. The soldier did not own the land but was only leasing it from the emperor. The land the soldier was tied to could be changed at the discretion of his superior. Each theme unit was capable of supporting neighboring themes during defense and offensive campaigns. The mobile units were flexible, serving the empire through to the 11th century. The themes were used to cut military costs and reduce the necessity for conscription since the land lease terms entailed that the soldier’s posterity would also serve in the military and work in a theme. The themes also allowed for equitable settlements on the conquered land.
The emperor reformed the imperial guard units into Tagmata armies. The Tagmata were primarily based in and around the capital Constantinople. The Tagmata were personally loyal to the emperor and paid in cash to instill an unwavering commitment to the emperor. Each Tagmata army unit comprised approximately 4,000 soldiers and was commanded by a Domestika. The Tagmata were mainly composed of the heavily armed cataphracts in the calvary. The Tagmata army also maintained large numbers of prestigious foreign units where some units comprised troops from a far-off land. The Tagmata army was not personally led into battle by the emperor but was commanded by a senior domestika. The Tagmata army was created to mitigate the challenges the themes instituted. The themes created a powerful military and political strategoi through the high level of autonomy given by the emperor. The themes thus developed a unique sense of identity, rivalry, and disdain for each other. This led to organized revolts by the strategoi within each other and also the capital. The Tagmata was developed to mitigate the risk of a significant uprising; thus, the themes armies were significantly decreased, and the soldiers were incorporated into the newly formed Tagmata army.
The Byzantine army tactical systems entailed a more minor and surgical army developed by absorbing equipment and doctrines from the empire’s most significant failures and enemies. The decrease in the army’s size provided the impetus for the Byzantine empire’s sophisticated approach to warfare. This led to the development of themes and Tagmata armies, who were vigorously trained to ensure the survival of the empire against civil war and the conquering of the kingdom. This latter approach was far more intelligent than the united Roman empire army since they did not deal with overly competent and extensive enemy armies.
Nicholas Morton, “Byzantine Military Tactics in Syria and Mesopotamia in the Tenth Century: A Comparative Study.” (2019): 245-247.
Brian Todd Carey, Allfree B. Joshua, and Cairns John. Warfare in the medieval world. Pen and Sword, 2006.
Yannis Stouraitis, A Companion to the Byzantine Culture of War, ca. 300-1204. Brill, 2018.
Ni Jianda, and Yue Li. “The introduction of Byzantine military systems during 11th-12th Century.” International Journal of Education and Management: 103.
 Morton, Nicholas. “Byzantine Military Tactics in Syria and Mesopotamia in the Tenth Century: A Comparative Study.” (2019): 245-247.
 Carey, Brian Todd, Joshua B. Allfree, and John Cairns. Warfare in the medieval world. Pen and Sword, 2006.
 Stouraitis, Yannis. A Companion to the Byzantine Culture of War, ca. 300-1204. Brill, 2018.
 Jianda, Ni, and Li Yue. “The introduction of Byzantine military systems during 11th-12th Century.” International Journal of Education and Management: 103.