In the mid-1st century BC, Republican Roman statesman Julius Caesar erected the first known bridges across the Rhine during his campaign in Gaul and led a military contingent across and into the territories of the local Germanic tribes. After several days and having made no contact with Germanic troops (who had retreated inland) Caesar returned to the west of the river. By 60 BC, the Suebi tribe under chieftain Ariovistus, had conquered lands of the Gallic Aedui tribe to the west of the Rhine. Consequent plans to populate the region with Germanic settlers from the east were vehemently opposed by Caesar, who had already launched his ambitious campaign to subjugate all Gaul. Julius Caesar defeated the Suebi forces in 58 BC in the Battle of Vosges and forced Ariovistus to retreat across the Rhine.