At the beginning of act 5 of the tragedy of julius caesar, which battle are the two armies preparing to fight?

At the beginning of act 5 of The Tragedy of Julius Caesar, the battle that are the two armies preparing to fight is the Battle of Philippi. The Battle of Philippi was the last fight in the Wars of the Second Triumvirate between the strengths of Mark Antony and Octavian and the powers of the tyrannicides Marcus Junius Brutus and Gaius Cassius Longinus in 42 BC, at Philippi in Macedonia.