Crossing the Rubicon
On 10th January in 49 BC, Julius Caesar and his troops famously crossed the Rubicon, the river marking the boundary between the province of Cisalpine Gaul and Italy. Taking the 13th Legion over this forbidden frontier constituted an act of treason and triggered civil war in Rome. According to the historian Suetonius, Caesar uttered the famous phrase ālea iacta est (“the die is cast”).