In the ensuing Battle of Bibracte, the Celts and Romans fought for the better part of the day. After a hotly contested battle, the Romans eventually gained victory. Caesar had set up his legions on a sloped hill, which put the Gauls at a disadvantage as they had to fight uphill. The Helvetii started the battle with a probable feint, which the Romans easily repulsed. However, the Boii and Tulingi allies then outmaneuvered the Romans and attacked their right flank. At this point, the Romans were surrounded. A heated battle ensued. The men in the legion's last line were ordered to turn their backs around. They now fought on two fronts instead of just being attacked in the rear, which Gilliver describes as a brilliant tactical decision. Eventually, the Helvetii were routed and fled. The Romans chased the now outnumbered Boii and Tulingi back to their encampments, killing the fighters as well as slaying the women and children.