Final answer:
After Caesar's death, Octavian and Marc Antony initially formed a cooperative alliance known as the Second Triumvirate, but their alliance was short-lived, eventually leading to conflict and the rise of Octavian as the sole ruler.
Step-by-step explanation:
Immediately following Caesar's death, Octavian and Marc Antony did work together. They formed the Second Triumvirate along with another general, Lepidus, in 43 BCE. This alliance took control of Rome, launched a campaign against Caesar's assassins, and ordered the execution of thousands of political opponents. However, their partnership was more a matter of convenience than genuine camaraderie, and soon they began plotting against each other to gain total control of the Roman Empire. The political cooperation did not last, and after pushing Lepidus aside, Octavian and Mark Antony divided the empire between them with Octavian taking Europe and Mark Antony the East. Not long after, their relationship deteriorated further, culminating in a civil war where Octavian ultimately defeated Marc Antony and Cleopatra, leading to their sui-cides and Octavian's rise as the first Roman Emperor.