“Crossing the Rubicon” is now an expression for passing the point of no return: this is the original incident from which it derives. In 49 BCE, Gaius Julius, at that time just a general and not yet Caesar, led his army across the Rubicon river, which marked the border of Rome: to cross it marked him as a treasonous leader of a revolt against the Roman state. Famously, he is said to have quoted the Greek playwright Menander, saying “alea iacta est” – “the die is cast.”
Julius would be successful in his quest for the leadership of Rome and its empire (much of which, particularly Gaul, added by his own military genius): which is why history knows him best as Julius Caesar.
By Illustrated by E. M. Synge – On the shores of Great Seas, Public Domain, Link
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