How did the Battle of Philippi affect Brutus and Cassius?

The Battle of Philippi resulted in the final destruction of the forces led by Marcus Brutus and Gaius Cassius, who had opposed the triumvirate of Octavian, Mark Antony, and Marcus Lepidus.1

The conflict unfolded in two stages:

• Cassius: During the first engagement on October 3, Cassius mistakenly believed his army had been defeated after Antony broke through his defenses. Consequently, he committed suicide.1
• Brutus: Following the death of Cassius, Brutus assumed command of the remaining forces. However, after a second major assault on October 23, his army was broken and surrounded by Antony’s cavalry. Facing certain defeat, Brutus also committed suicide, leading to the surrender of his remaining troops and the total collapse of their resistance.1

This defeat effectively ended the efforts of those who sought to preserve the old Republican constitution of Rome following the assassination of Julius Caesar.1