The Cimbrian or Cimbric War (113–101 BC) was fought between the Roman Republic and the Germanic and Celtic tribes of the Cimbri and the Teutons, Ambrones and Tigurini, who migrated from the Jutland peninsula into Roman-controlled territory, and clashed with Rome and her allies. The Cimbrian War was the first time since the Second Punic War that Italia and Rome itself had been seriously threatened.It was the first of many confrontations with Germanic tribes in Roman history that would last for centuries.
The timing of the war had a great effect on the internal politics of Rome, and the organization of its military. The war contributed greatly to the political career of Gaius Marius, whose consulships and political conflicts challenged many of the Roman Republic's political institutions and customs of the time. The Cimbrian threat, along with the Jugurthine War, allegedly inspired the putative Marian reforms of the Roman legions, a view now contested by modern historians.