Caesar continued his conquests, invading Britain and waging another successful war against the Gauls. While he was away, Crassus died in battle with the Parthians, and Pompey, who had become Caesar's rival and enemy, was elected consul. Pompey and the senate decided to try to strip Caesar of his command and recall him to Rome. If he returned to Rome without an army, Caesar would have been prosecuted for corrupt consuling and also probably exceeding his authority as governor. So instead, he returned with the 13th Legion. He crossed the Rubicon River, famously saying, the die is cast, or possibly, let the die be cast. Sorry, Thought Bubble, sources disagree.