Also, Jacta alea est! Supposedly spoken by Julius Caesar, 49 B.C., when he crossed the Rubicon to challenge the Senate and Pompey's forces for supremacy of Rome. Crossing the Rubicon river resulted in the civil war and Pompey's defeat by Julius Caesar's forces.
Suetonius wrote that Caesar said, "Let us go forward whither the signs of the gods and the injustice of our enemies call us. The die is cast!" Another translation says, "Let us march on, and go wherever the tokens of the gods and the provocations of our enemies call us. The die is cast!" or "The die be thrown!"
What Caesar meant is that by crossing the Rubicon, he will have passed a point of no return, and fate would decide the outcome.
Also written as Jacta alea est!