January 16: Beginning of the Roman Empire (27 BC)

Gaius Julius Caesar Octavianus is granted the honorific title Augustus (the revered one) by the Roman Senate and became the first emperor of the Roman Empire on January 16, 27 BC. Augustus reigned the Roman Empire until his death on August 19, AD 14 for 40 years and 215 days. Born Gaius Octavianus Thurinus, he was posthumously adopted by his great-uncle Gaius Julius Caesar via his last will and testament in 44 BC and was officially called Gaius Julius Caesar. The official title as the Emperor was Gaius Julius Caesar Augustus. After the assassination of Julius Caesar, Octavianus formed a military dictatorship, known as the Second Triumvirate, with Marcus Antonius and Marcus Aemilius Lepidus and then defeated the the two: Lepidus was driven into exile and Antonius committed suicide after the defeat at the Battle of Actium by Agrippa in 31 BC. Octavianus then restore the appearance of the Roman Republic and spent four years to determine the framework by which a formally republican state can be ruled by a sole ruler, which resulted in the Roman Empire.