Every male Greek citizen was required to serve in either the army or the navy. When they turned 18, Athenian men were trained for two years in military discipline and served as police, prison guards, and on garrison duty. They could be called to fight if a war broke out. The Greeks were disciplined soldiers and were in great demand as mercenaries. One of the reasons that there were so many Greek mercenaries is that soldiering for hire was one of the few ways many Greek men could make a good living. Most fighting was done by citizen-soldiers in small armies.
With water on three sides, the Greeks also maintained a navy. Poorer citizens could become oarsmen in the fleet. Wealthier Athenians who could afford the equipment, which they had to pay for themselves, joined the army as hoplites, or foot soldiers. The hoplite’s equipment included helmet, shield, breastplate, shin-guards, sword, and spear. The armor was made of bronze or iron plates sewn onto pieces of leather. Soldiers wore bronze helmets with guards that also protected their cheeks and noses. On top of the helmets they usually had a crest of feathers or horsehair. They wore wool cloaks for warmth.
In Alexander’s time, the Athenians elected their generals and admirals. A common soldier in one war might be a general in the next. Armies were made up primarily of infantry. Cavalry did not play a large part, because horses were expensive to maintain and Greece’s mountainous terrain made them less practical.
Before Alexander’s father, Philip II, came to power, the Macedonian army was primarily made up of poor farmers who served as amateur soldiers during part of the year. Philip turned these amateurs into skilled soldiers, creating a professional army in Macedonia. Under Philip, soldiers trained all year long, making long marches with heavy packs to build their strength. Philip also developed a formidable Macedonian cavalry. As in
Greece, members of the cavalry had to provide and feed their own horses, making this a position for wealthy noblemen.
The strongest military branch in the Persian Empire was the navy, which included about 400 warships built by men from Phoenicia. Military leadership was limited to Persian nobles, but all Persian boys entered the military when they turned 18. Males from ages 15 to 50 could be drafted into the army if they were needed. When they returned, they were expected to marry additional wives and have a lot of children.