"The Die is Cast" means a decision has been made or an occurrence has happened that cannot be changed.

The 'die' in this phrase refers to dice used in games of chance. This phrase was made famous by Julius Caesar when he led his army in 49 BC across the Rubicon River into the northernmost border of Rome's territory and committed to civil war. Hence the phrase Cross the Rubicon has the same origin, meaning and usage.

Use Example - I just turned in my resignation letter. The die is cast, time to start packing my bags.

Source Tags : Julius Caesar