Catapults are a form of early artillery that were used to fire projectiles at the enemy. They were first invented by the Ancient Greeks but were later adapted and improved by the Romans.
Catapults were first used by the Ancient Greeks as a siege weapon in the fourth century BC. The Romans did not invent the catapult, but they significantly developed and improved its technology.
The first Greek catapults were like mechanized slingshots or crossbows. The Romans took this idea and made their own versions that could be used against soldiers on the battlefield or as heavy siege weapons.
The first catapult was invented by Dionysus, the Greek ruler of Syracuse, in preparation for a war with Carthage. He was seeking to gain a military advantage by increasing the size and power of arrows that his army was able to shoot.
This catapult was like a large crossbow with a timber frame and a strong string made of animal sinew. When the tensed string was released it propelled an arrow much further than any human could throw.
The catapult was used by Dionysius to great effect at the Siege of Motya in 397 BC. The catapult’s success meant that it was adopted as a standard weapon in the Greek arsenal.
Alexander the Great used catapults on the battlefield rather than just as a siege weapon. Its ability to attack opposing armies at long range was a factor in Alexander’s military success.
A more sophisticated and more powerful version of the catapult was developed called a ballista. This used large, coiled springs as the firing mechanism, rather than just a tensed string, and could fire stones as well as arrows.
Historians of technology have suggested that catapults pre-dated this invention. Archaeological evidence of round stones and a carved relief from a palace in the Assyrian city of Nineveh have been used to argue that catapults were used at the siege of Lachish in 701 BC.
The evidence is scant, and the claim appears to be wishful thinking. The carvings principally show soldiers using hand-held slingshots rather than a mechanical device.
Others have claimed that catapults were used in Ancient Egypt, but again there is no hard evidence. A different type of catapult was developed in China around the same time as Dionysius, but the Greeks are given the credit for the invention of the catapult.
The Romans witnessed the success of Greek catapults and began to develop their own versions. One of the first instances of the Romans using a catapult was in the siege of Syracuse in 213 BC when they successfully captured the city.
The Romans innovated with catapult technology and made smaller and more portable devices known as scorpions and cheiroballistra that were specifically designed as field artillery. These were used to great effect by Julius Caesar in the Gallic Wards and in the conquest of England in 55 BC.
One of the best descriptions of the construction and use of Roman catapults comes from the writings of the Roman engineer Vitruvius. His book De Architectura, written around 30 BC, contained descriptions of everything from temples and aqueducts to clocks.
In the section on machines, he outlined the principles for constructing catapults, for throwing arrows, and ballistae, for throwing stone balls. He gave very detailed instructions and proportions for them, based on the size of the arrow or ball that was to be thrown.
His instructions are very complex, and he warns that only those with a good understanding of geometry and mathematics should attempt to build them. This demonstrates the sophistication of Roman engineering that enabled these types of machine to be created.
Another Roman innovation was a catapult known as an onager, which was developed in the fourth century AD. This was a very large siege weapon that fired heavy rocks.
These weapons had a long throwing arm fitted with a large cup in which rocks or other projectiles could be placed. When the mechanism was fired, a spring would propel the arm upright and send the rocks flying towards the besieged fortification.
The term onager meant ‘wild ass’ and was applied to this machine as its action resembled the kick of a donkey. It was a highly effective form of heavy artillery and was the precursor to the type of siege weapon that was used in medieval times.