The first Roman Emperor was Augustus, a nephew and adopted son of Julius Caesar. Julius Caesar was not emperor, though he held all the power in the Roman Republic. When he was assassinated, Augustus...
Tiberius was at first least likely to succeed Augustus. Augustus' designated heirs was at first Marcellus, his nephew and his daughters husband. When he died in 23 BC, Augustus married his daughter...
A brief definition of a Roman Emperor can be taken from the link below. "The Roman Emperor was the ruler of the Roman State during the imperial period (from about 27 BC onwards). The Romans had no...