Army, Israel

The Spartan Army was one of the earliest known professional armies. Boys were sent to a barracks at the age of seven to train for being a soldier. At the age of thirty they were released from the barracks and allowed to marry and have a family. After that, men devoted their lives to war until their retirement at the age of 60. Unlike other civilizations, whose armies had to disband during the planting and harvest seasons, the Spartan serfs or helots, did the manual labor.
This allowed the Spartans to field a full-time army with a campaign season that lasted all year. The Spartan Army was largely composed of hoplites, equipped with arms and armor nearly identical to each other. Each hoplite bore the Spartan emblem and a scarlet uniform. The main pieces of this armor were a round shield, a spear and a helmet.
• Ancient Rome
The Roman Army had its origins in the citizen army of the Republic, which was staffed by citizens serving mandatory duty for Rome. Reforms around 115 BC turned the army into a professional organization which was still largely filled by citizens but citizens who served continuously for 25 years before being discharged.