What were the entry requirements for the Roman army?

The entry requirements for becoming a soldier in the Roman army were relatively basic as there were Roman soldiers in many Roman provinces, protectorates, and client states from France to the Levant. The Roman Empire, wanting to maximize the number of soldiers at its disposal, made it a point to keep the entry requirements basic and to keep as many battle-ready soldiers as possible. The requirements for entrance into the Roman army were as follows: A man must be a freeborn Roman citizen, able to pass a medical exam, be at least 5′ 8″ tall, be at least 20 years of age, be able to march at least 20 miles in a day, and be willing to commit to 25 years of service to the Roman army. As you can see, the requirements were all about the physical abilities and the level of loyalty that each prospective soldier possessed. Roman soldiers were measured on their ability to act rather than to reason, and they were expected to do whatever their centurion told them to do in the heat of battle. As a reward for their service, when a soldier completed his 25th year of duty, the Roman government gave him a plot of land and a pension for he and his family to live off of for the rest of their days.

It should be noted that there was a significant number of non-Roman soldiers that served in Roman auxiliary units across the Roman Empire. The Roman Empire routinely absorbed foreign-born soldiers into auxiliary or “helper” units to assist Roman soldiers. These soldiers were often times natives of a country that the Romans annexed. These auxiliary soldiers were held to the same standards of age, fitness, and tenure as the Romans were. As a reward for their service, the Roman government granted the soldiers serving in auxiliary units full Roman citizenship at the end of their tenure as soldiers.