How did Octavian become Augustus after Julius Caesar’s assassination?

After the assassination of Julius Caesar in 44 BCE, his 18-year-old grandnephew and adopted heir, Octavian, returned to Rome to claim his inheritance. He initially navigated a volatile political landscape, eventually forming the Second Triumvirate with Mark Antony and Marcus Lepidus to consolidate power and eliminate Caesar’s assassins.123

The alliance eventually fractured as Octavian and Antony became rivals. After stripping Lepidus of power, Octavian waged war against Antony and Cleopatra, decisively defeating them at the Battle of Actium in 31 BCE.345

Following his victory, Octavian became the undisputed master of the Roman world. In 27 BCE, he ostensibly restored the Republic while retaining significant control, and the Senate granted him the title Augustus. By concealing his autocracy behind traditional republican forms and assuming powers such as imperium majus and tribunicia potestas, he established the principate and became Rome's first emperor.562