Final answer:
Augustus, originally known as Octavian, became the commander and permanent governor of the imperial provinces, consolidating his control over the Roman army and marking the transition from the Roman Republic to the Roman Empire.
Step-by-step explanation:
Due to the agreement, Octavian, known as Augustus after 27 BCE, became the commander and permanent governor of the imperial provinces in the Roman Empire. After forming the Second Triumvirate and defeating Julius Caesar's assassins, Octavian rose to unparalleled power. In 27 BCE, he was granted the title 'Augustus' by the Senate, which recognized him as the Princeps Senatus (leader of the Senate) and simultaneously appointed him proconsul of all Roman frontier provinces. As a result, he effectively controlled the entire Roman army. The Senate’s actions ensured Octavian's role was cemented not only in military matters but also in the governance of the imperial provinces, indicating a shift from the Roman Republic to the beginnings of the Roman Empire under his rule as the first emperor.