Final answer:
Augustus, originally known as Octavian, defeated three rivals to become the first emperor of Rome, replacing the faltering republic system with a structured imperial rule and enacting reforms that strengthened the Roman military and integrated the provinces into the empire through Romanization policies.
Step-by-step explanation:
The individual who defeated three rivals to become the emperor of Rome was Augustus, known as Octavian before his ascent to the throne. Augustus notably triumphed over Marc Antony, his last significant challenger, solidifying his control over Rome after the tumultuous events following Julius Caesar's assassination. Augustus envisioned a strong and centralized Rome where the republic's faltering system was replaced with a structured imperial rule. He presented a vision of stability, enacted reforms, and embarked on building programs that symbolized Roman strength and unity.
Augustus's reign marked the end of a series of civil wars and brought about a period known as Pax Romana, which saw the Roman Empire flourish in terms of economic prosperity and cultural achievements. His reforms reshaped the military by providing lands for veterans, thereby professionalizing the Roman legions. Augustus also promoted the integration of the provinces into the empire through Romanization policies, which included granting Roman citizenship and encouraging the spread of Roman culture. His vision was of a Rome where the emperor embodied the roles of a general, magistrate, and godlike figure, as seen in the various representations through statues and portraits. This model of leadership deeply influenced the structure and concept of imperial rule in the Roman Empire and established a precedent for his successors to follow.