Julius Caesar was not the first emperor of Rome, in fact, he was the last dictator. He is often mis-represented as the first Julio-Claudian Emperor, but in truth this title goes to his adopted son, Octavian.

The Random House Dictionary defines an empire as "an aggregate of nations, tribes, clans, or peoples governed by one supreme ruler." In an empire, one person reigns over many groups of people held together by a strong military and a well-formed bureaucracy.

A dictator in ancient Rome was the person who was given supreme authority for six months during a time of crisis. Today, "dictator" has come to apply to a person who assumes complete authority over an area typically against the will of the people.

Originally, Caesar was the title for a leading military general or dictator, though it later came to mean emperor, and then again changed its meaning to the second-in-command to the emperor after Rome split into two smaller empires under Constantine.

Julius Caesar was a Caesar and a dictator. In 59 BCE, Julius Caesar was elected to the First Triumvirate along with Crassus and Pompey. He was a general in the Roman army. He took an army, captured more territory in Gaul, then took his army back to Rome and killed his two rivals, taking complete control of the government. He did this as a dictator - against the will of the people who elected him.

Octavian was the first of the Julio-Claudian emperors, who ruled until the death of Marcus Aurelius. Octavian was the grandnephew and adopted son of Julius Caesar. He was elected to the second triumvirate with Marc Antony 13 years after Julius' death, as which time he took the title "Caesar." When his final opponents, Cleopatra and Marc Antony, committed suicide in 31 BCE, Octavian took power and changed his name to Augustus Caesar. He founded a true empire, with himself as the sole ruler. Julius Caesar was the last dictator; Octavian was the first Julio-Claudian emperor.