What does it mean to cross the Rubicon

Rubicon is a river that flowed in the Roman Empire. And it is known mainly due to the expression "to cross the Rubicon", meaning the adoption of some irrevocable decision. Its history is connected with the time when Julius Caesar was not an emperor, but was only a military leader (proconsul), and Rome was a republic. By law, the proconsul had the right to lead an army only outside Italy. However, on January 10, 49 BC. e. he with his army approached the Rubicon. But he was not sure of the strength of his army and therefore hesitated, because if he failed, he would be subjected to public shame and torture. He crossed the Rubicon and became emperor after the civil war.

After Caesar crossed the Rubicon, the river was on everyone's lips for a long time, until Emperor Augustus reorganized the administrative division of Italy and included the modern north of Italy in it. As a result, the Rubicon ceased to be Italy's northern border. After the rapid expansion of Roman possessions, the word "Rubicon" gradually disappeared from the topographic map.

After the fall of the Roman Empire and during the first centuries of the Middle Ages, the coastal plain between Ravenna and Rimini was flooded many times. The Rubicon, along with other small rivers in the area, often changed its direction of flow. Therefore, in order to supply the area with water after the revival of agriculture after the Middle Ages, as well as to prevent other floods and regulate flows, during the 14th and 15th centuries, they began to build dams and dig drainage systems. As a result, these rivers eventually became the direct streams that they actually are today.

In 1933, serious attempts were made to find the location of the river. The Fiumicino River, crossing the city of Savignano di Romagna (now Savignano sul Rubicone), has been officially identified as the former Rubicon. Final evidence supporting this theory was found only in 1991, when scientists proved that the distance from Rome to the Rubicon was about 200 kilometers.

Source: Wikipedia