manner_of_death messalina
The Roman Empire ( Koine and Medieval Greek :    , tr . ) was the post - Roman Republic period of the ancient Roman civilization , characterized by government headed by emperors and large territorial holdings around the Mediterranean Sea in Europe , Africa and Asia . The city of Rome was the largest city in the world BC AD , with Constantinople ( New Rome ) becoming the largest around 500 AD , and the Empire ' s populace grew to an estimated 50 to 90 million inhabitants ( roughly 20 % of the world ' s population at the time ). The 500 - year - old republic which preceded it was severely destabilized in a series of civil wars and political conflict , during which Julius Caesar was appointed as perpetual dictator and then assassinated in 44 BC . Civil wars and executions continued , culminating in the victory of Octavian , Caesar ' s adopted son , over Mark Antony and Cleopatra at the ___MASK66___ of Actium in 31 BC and the annexation of Egypt . Octavian ' s power was then unassailable and in 27 BC the Roman Senate formally granted him overarching power and the new title " Augustus ", effectively marking the end of the Roman Republic . Augustus ( 23 September 63 BC  19 August 14 AD ) was the founder of the Roman Principate and considered the first Emperor , controlling the Roman Empire from 27 BC until his death in AD 14 . Valeria Messalina , sometimes spelled Messallina , ( c . 17 / 20 -- 48 ) married ( as his third wife ) the Roman Emperor Claudius . She was a paternal cousin of the Emperor Nero , a second - cousin of the Emperor Caligula , and a great - grandniece of the Emperor Augustus . A powerful and influential woman with a reputation for promiscuity , she allegedly conspired against her husband and was executed on the discovery of the plot . Her notorious reputation arguably results from political bias , but works of art and literature have perpetuated it into modern times . The term Julio - Claudian dynasty refers to the first five Roman emperors  Augustus , Tiberius , Caligula , Claudius , and Nero  or the family to which they belonged . They ruled the Roman Empire from its formation under Augustus in the second half of the 1st century ( 44 / 31 / 27 ) BC , until AD 68 when the last of the line , Nero , committed ___MASK44___ . Caligula , properly Gaius Julius Caesar Augustus Germanicus ( 31 August AD 12  24 January AD 41 ) was Roman emperor from AD 37  41 . Born Gaius Julius Caesar Germanicus ( not to be confused with Julius Caesar ), Caligula was a member of the house of rulers conventionally known as the Julio - Claudian dynasty . Caligula ' s biological father was Germanicus , and he was the great - nephew and adopted son of Emperor Tiberius . The young Gaius earned the nickname " Caligula " ( meaning " little soldier ' s boot ", the diminutive form of " caliga ", hob - nailed military boot ) from his father ' s soldiers while accompanying him during his campaigns in Germania .