The phrase "The die is cast" is famously attributed to Julius Caesar. According to historical accounts, Caesar uttered this phrase as he crossed the Rubicon River in 49 BCE, which was a significant act of defiance against the Roman Senate. By crossing the Rubicon, he effectively declared war on the Senate, putting himself in conflict with the established political order and igniting a civil war for control over Rome. This phrase embodies the idea of taking irrevocable action, as Caesar was well aware that crossing the river meant there was no turning back, thus altering the trajectory of Roman history.