After Rome was sacked by the Senones in 390 BCE, they regrouped and formed an alliance of the city states. They deployed thoroughly trained soldiers in the north western frontiers to protect Rome from further attacks. These soldiers were divided into two groups, "Legionaries" and "Auxiliaries", Legionaries were Roman citizens where as Auxiliaries were recruited from tribes and allies of Rome. They eventually defeated the Gauls and gained total control of the Italian peninsula as well as North Western Europe. The Romans never used complex weapons, instead they chose to use the more simple and unusual weapons of warfare. The armor and weapons were used under excellent supervision, great leadership and discipline that enabled the Romans to create superior military forces, both regular and irregular armies including mercenaries and allies, that were able to conquer their opponents.