|Millennium:||1st millennium BC|
|101 BC by topic|
|Wikimedia Commons has media related to 101 BC.|
Year 101 BC was a year of the pre-Julian Roman calendar. At the time it was known as the Year of the Consulship of Marius and Aquillius (or, less frequently, year 653 Ab urbe condita). The denomination 101 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
- The Roman consuls Gaius Marius and Manius Aquillius defeat the Cimbri in the Battle of Campi Raudii (or Battle of Vercellae).
- Cleopatra III of Egypt assassinated by her son Ptolemy X Alexander I (b. 161 BC)
- Boiorix, king of the Cimbri tribe, killed at the Battle of Vercellae.