 The first historical mention of the Cherusci occurs in Book 6.10 of Julius Caesar's "De Bello Gallico", which recounts events of 53 BC.Caesar relates that he crossed the Rhine again to punish the Suebi for sending reinforcements to the Treveri.He mentions that the Bacenis forest (a relatively impenetrable beech forest, possibly the Harz) separated the territory of the Cherusci from that of the Suebi.