Julius Caesar: The Roman general who famously uttered "Alea iacta est" as he crossed the Rubicon River with his army, defying Roman law and sparking a civil war.
Rubicon River: A river in northern Italy that marked the boundary between Italy and Gaul. Crossing it with an army was forbidden by Roman law without permission from the Senate.
Civil War: A conflict between different groups within the same country or empire. In ancient Rome, Julius Caesar's crossing of the Rubicon led to a civil war against Pompey and his supporters.