There have been few military units as devastating in their time as the Greek phalanx. Heavily armored and insanely well trained, these soldiers were capable of standing against any and all challengers. Fighting for one's country was an unswerving responsibility among the Greek city-states. Even the poets of the time were tough bastards; most of them wrote only of warfare, courage, resolve and beating the snot out of your enemies.
Greek warriors fought in a phalanx; a unit of heavily armored men that fought in rows, with large shields (hoplons), long spears and short swords. The wealthy made up the majority of the infantry. Those with money were the only ones who could afford the horrendously expensive armor and spears that made a Hoplite warrior. The poorer troops were thrown into skirmishing units that were armed with slings, bows and spears and wore light armor. These skirmishers were generally only on the outskirts of the battle. This strikes me as particularly ironic because in modern day warfare it seems like the poor are the ones on the front lines while the wealthy are ... well ... on their yachts, laughing and chugging boat-drinks thousands of miles away. My how Democracy has changed over the years.
The Greek Hoplites fought primarily with spears. A typical Hoplite battle consisted of opposing units charging each other with their shields up. The two units would crash together and start shoving. If you've ever seen a rugby scrum, then you get the general idea of phalanx warfare. Only, these rugby players are extremely well armored, and are jabbing long, lethal spears over the top of their shields trying to kill as many of the opposing players as possible.
The shoving and stabbing would continue until one of the units started to falter. The first phalanx to start breaking up usually ended up getting routed and usually massacred. If neither unit gained any definitive advantage for a time, the fighting broke down to a big sloppy melee. Formations vanished and chaotic carnage would reign, with soldiers trying to keep themselves alive while killing as many of their opponents as possible. It was at this point that most Hoplites would switch to their short sword.
Phalanx units were funny things. Each man depended on every other man to hold the formation. If enough of your fellow soldiers lost their courage, your unit would be lost. It was an interesting practice for hoplite commanders to divide their very best soldiers among the front line and the very last line of their units. The front line fighters needed to be strong because they were slamming headlong into their opponents. But the back line warriors needed to be experienced because they needed to keep all of the other soldiers from running away. They would shout encouragement, push against the lines ahead of them and, if necessary, threaten the other soldiers to make sure they kept their minds on the business at hand. Running from a fight was considered cowardly, not just because you lost your nerve, but also because you doomed your mates to a horrible fate. It was said that a Greek should never die with a wound in his back.
See Strongblade's Spartan Spear