crossing the rubicon

On This Day In Ancient History — January 10 49 BCE — Crossing the Rubicon


“Crossing the Rubicon” is a pretty common phrase that means something like “going past the point of no return.” Once you cross a proverbial Rubicon, you’ve set in motion a course of action from which you cannot retreat. But what does it really mean? Julius Caesar crossing the Rubicon is easily the most consequential river crossing in the history of Western civilization; the homey Caesar would have killed at Oregon Trail. 

The Rubicon and Why It Matters

Rome was divided into different provinces; they were like states. Each province had a governor called a proconsul. The governor of each province had imperium, which was the power to command an army. However, no governor was allowed to enter Italy and definitely not with an army. Why would you need to be in Italy with an army, huh? That’s an aggressive move. 

Caesar was the governor of multiple provinces, one of which was Cisalpine Gaul (Gaul on the same side of the Alps as Italy). The Rubicon River, a small river in northern Italy, was the border between Cisalpine Gaul and Italy. Crossing the Rubicon would mean crossing into Italy proper. 

So, Caesar bringing an army across the Rubicon means that he was bringing an army into Rome; to the Roman senate, that was the same as an invasion. 

Why’d He Do It

Julius Caesar spent his entire professional life running up huge debts and doing crimes. However, consuls and governors were immune from prosecution while they were in office. Caesar’s term as governor was nearing its end in 49 BC. He wanted to run for consul to extend his immunity; however, he needed to physically be in Rome to run for office. You see the conundrum. He needed to run for office so that he could stay immune from prosecution. However, to run for office, he needed to give up his governorship and thus, his immunity. As soon as private citizen Julius Caesar set foot in Rome, he would have been arrested. 

So, instead, Caesar returned to Rome to run for consul. He needed a legion though because his goon squad was the only thing keeping him from being arrested. The senate didn’t take kindly to Rome being invaded, they selected Pompey to fight Caesar’s legions, and the resulting civil war destroyed the republic. 

The Die Is Cast

In his own account of the war, Caesar doesn’t mention crossing the Rubicon. He does mention marching to the city directly south of the river, though. Supposedly, as his legion marched across the river, Caesar said “alea iacta est”, which is Latin for “the die is cast.” This means, essentially, that the dice have already been thrown, and the gambling has begun.

On this day in ancient history, Gaius Julius Caesar gambled with the fate of democracy and essentially banished it from Western civilization for the next 1800 years. Congrats, Gaius, you won.