The Roman cavalry was certainly not the primary weapon of the Roman army, which heavily relied on its infantry to win battles and wars. However, the cavalry provided several vital services which were essential for expanding Rome's territories.

The Roman cavalry's functions on the battlefield included:

  • Scouting and intelligence gathering
  • Skirmishing conflicts before the battle began
  • Flanking maneuvers (Charging into the flank or rear of the enemy's units causing mayhem)
  • Protecting against the enemy's cavalry maneuvers
  • Chasing down any fleeing enemy

During the Roman Kingdom and much of the Roman Republic (753 BCE to 107 BCE), each soldier had to provide his own equipment. That meant only the richest of Rome's citizens were cavalrymen as they would have to provide their own horse and it's upkeep. During this period, the cavalry was lightly armored. It had high mobility allowing to be moved around the battlefield very quickly.

As the Roman Republic progressed, the cavalry became better equipped:

  • Coolus Helmet: provided good protection to both the front and back of the head. A large rim helped to protect against enemy strikes.
  • Hexagonal Shield: which would have been roughly 125 cm in length and 55 cm wide. These shields were constructed with several layers of wood and then reinforced with a steel boss.
  • Body Armour: despite this changing several times through the centuries it is accepted that in the later Roman Republic and throughout most of the Roman Empire that bronze breastplates were used.
  • Spear (hasta): during the Roman Kingdom and much of the Roman Republic the hasta was used by the cavalry. It was very good when charging into enemy infantry.
  • Long sword (spatha): in the latter part of the Roman Republic the spatha replaced the hasta due to its superior hand to hand capabilities.

After the Marian reforms (107 BCE) and the establishment of the legions, each legion had 300 cavalrymen. These were divided into ten squadrons of 30 cavalrymen each.


Roman Auxiliary Cavalry (alae)

The Roman auxilia was established in around 30 BCE, much of Rome's cavalry forces would be recruited from the auxiliary's ranks. The 'alae' were the cavalry units of the auxilia. The auxilia were usually organized into units of 500 cavalrymen commanded by a Roman born prefect. Double strength units had a total of 800 riders. There were also part cavalry part infantry auxilia units (600 soldiers in total: 480 infantrymen and 120 cavalrymen.

The alae were specialised units so not all units were identical. Much of the auxilia cavalry was equipped with mail armor similar to the cavalry of the Roman legions. However, other units such as the 'equites cataphractarii' were very heavy shock cavalry. However, there were also lightly armored cavalry units which could be moved around the battlefield quickly.

Read more about the Roman auxiliary's cavalry units



Importance of Horses

Beyond the battlefield, horses were of importance for a variety of reasons.

  • Horses were the quickest form of transport. If the Senate had to send a message to a general on the front lines, horse messengers were the fastest way of communicating.
  • Horses were also important for logistics and transporting supplies to every corner of the Roman Empire.

Cavalry horses also placed a large strain on an army's resources. They required large amounts of food and water; consuming a kilo of barley and twenty-five liters of water each day.

We can also measure the effects of selective breeding during the Roman Republic and Roman Empire. The army obviously wanted the tallest and strongest horses for their cavalry. During the start of the Roman Empire, the average height of a horse was 120 cm, towards the end of the Roman Empire horses were as tall as 150 cm in some regions. An increase of 25% over several centuries.

The average life expectancy of horses belonging to the Roman cavalry was only around six to ten years old.