Ultimately what started the Social War?
Between 135 BC and 71 BC there were three "Servile Wars" involving slave uprisings against the Roman state. The third and final uprising was the most serious, involving ultimately between 120,000 and 150,000 slaves under the command of the gladiator Spartacus. In 91 BC the Social War broke out between Rome and its former allies in Italy when the allies complained that they shared the risk of Rome's military campaigns, but not its rewards. Although they lost militarily, the allies achieved their objectives with legal proclamations which granted citizenship to more than 500,000 Italians.