After the tragic defeat of the Romans at Cannae in 216 BCE Rome was so deprived of recruits that there were even enlisted slaves to the army. They were called voluntarii or volones.
In a situation when Rome was beginning to be short of free-born men capable of fighting, the Romans had no other choice. Apparently, 8.000 young slaves formed a separate unit. They received weapons (from public expenses), and in exchange for service they were promised freedom.
Consul in 215 BCE – Tiberius Gracchus (grandfather of the famous Gracchi brothers) – took command of the army of slaves. Gracchus apparently showed great gentleness for slaves who tried to use the situation to escape. After one of the victorious battles, he liberated some of the slaves in his legion, who nevertheless remained with him. Thanks to his attitude, he earned the respect of soldiers.
In 214 BEC Gracchus became a proconsul and still commanded a legion of slaves and a regular army. During this time, he fought in central and southern Italy with Hannibal’s troops.
Finally in 213 BCE he became consul again and in 212 BCE died in Lucania during a bath. The commander was to die by deception, but Hannibal arranged for him a proper funeral and returned his ashes to Rome. However, we do not know further fate of slaves in the Roman army.