A prime example of Roman loss in battle was the Battle of Teutoburg Forest in AD 9, where three entire legions led by Publius Quinctilius Varus were destroyed by Arminius, leader of the Cherusci, an apparent Roman ally. Augustus retaliated by dispatching Tiberius and Drusus to the Rhineland to pacify it, which had some success although the battle of AD 9 brought the end to Roman expansion into Germany. Roman general Germanicus took advantage of a Cherusci civil war between Arminius and Segestes; they defeated Arminius, who fled that Battle of Idistaviso in AD 16 but was killed later in 21 due to treachery.