After Caesar's death, two of his partisans (Antony and Lepidus) and his adopted son Octavian formed the second triumvirate. They were twice given 5 years of supreme power. During this time, they slaughtered their enemies and revolutionized the old republic. At this point, Caesar's adopted son Octavian took Italy and part of Gaul, Antony took the rest of Gaul and Lepidus was given Africa. Antony cultivated his region to fund the 100,000 veteran soldiers, and he and Octavian consolidated their positions. When Antony was denied admittance to visit Italy, though, a civil war nearly erupted before an agreement was reached. Neither Antony nor Octavian were ready to fight for supremacy.
When the ruler (Sextus) of nearby islands restricted Rome's grain supply, Octavian acknowledged his power and stabilized their relationship by marrying into the family. He eventually divorced the family, though, to marry a fellow Roman's wife. The grain supply was again disrupted, and Octavian used Antony's assistance to defeat Sextus. Shortly thereafter, Lepidus tried to seize Siciliy but his troops joined Octavian and Africa was thereby acquired without bloodshed. The legions simply refused to fight against Caesar. This gave Octavian control of all the West and Antony control of the East.
Antony and Cleopatra formed a lusty power couple. Yet when they confronted Octavian for total domination, Octavian won. He was now not only master of the world but also unified all of Rome into a peaceful superpower. For the first time in 700 years, the bruised and exhausted Rome was peaceful. Octavian was credited with this peace. In addition, he had acquired for Rome more land than ever before. At this point, by carefully avoiding the mistakes of his predecessors, he stopped countless orgies of violence before they ever began. For example, instead of having 70 legions he only had 26. This prevented the military from revolting and trying to seize control. Also, he gave the veterans generous retirement plans. By already establishing credibility as a successful politician capable of glorifying Rome, the senate was more likely to compromise with him to avoid another civil war.