Julius Caesar’s Invasion of Parthia
Julius Caesar planned to invade Parthia in 44 BC. It was to be a massive endeavor with the largest force he had ever led: 16 legions and 10,000 cavalries, in addition, to support troops. As a preliminary, he planned to first invade and conquer the kingdom of Dacia, roughly modern Romania, which he calculated could be accomplished by the end of 44 BC. The following spring, he would move on to Parthia.
Parthia was no pushover, as evinced by the Battle of Carrhae in 53 BC, where a Parthian cavalry force of 10,000 had all but annihilated a much larger Roman army of roughly 50,000, led by Caesar’s fellow Triumvir, Crassus. In 38 BC, Mark Antony invaded Parthia with an even larger force than that which Caesar had planned to use, numbering over 100,000 legionaries, 24,000 auxiliaries, and 10,000 cavalry, only to meet with disaster.
However, neither Crassus nor Mark Antony were in Caesar’s league as generals, while Caesar was Caesar – an all-time great military mind. And Parthia was not invulnerable to a Roman army led by a commander of genius. A century and a half later, the emperor Trajan did exactly what Caesar had planned, conquering Dacia, then successfully invading and defeating Parthia, seizing its capital city of Ctesiphon, annexing Mesopotamia, and dictating a highly favorable peace treaty.
It is not inconceivable that Caesar could have accomplished the same in the 40s BC. However, he would never get the opportunity to try: three days before he was to leave Rome for the Parthian campaign, Caesar was assassinated by Roman senators.