The first actual civil war between Romans was Sulla's first civil war (88--87 BC), between the forces of Lucius Cornelius Sulla's supporters and those of Gaius Marius. The final civil war of the Roman Republic, between Octavian and Marc Antony, occurred in 30 BC.
The Result of the civil wars was the end of the Roman Republic and the beginning of rule by emperors. The final war was a clash over who would become the sole ruler of Rome. Octavian won, established his own absolute personal rule and became the first Roman emperor and was bestowed the title of Augustus (with which is is known for the period when he was the emperor). This was formalised in the Second Settlement between the senate and Octavian, and historians use this date to mark the beginning of the 503-year period of rule by emperors.
victorious generals became dictators