The early medieval army was composed of about one-third mounted knights, a few professional soldiers, and the rest were peasants who were conscripted for the battle. The soldiers wore whatever they had available; most were clothed in a leather jerkin with iron rings. They carried a battle shield for better protection.
The typical knight wore steel-mail hose on his legs. On his upper body the first layer of clothing to protect from the steel hauberk was made from felted hair or quilted cotton. That particular garment is now referred to as a gambeson. The next upper body mail article was the riveted steel hauberk, and it often extended to mid-thigh or below his knees. This armor could weigh between 19 to 60 pounds, dependent upon the amount of money the knight could give the craftsman. The lighter pieces naturally were more expensive.
The hauberk was subject to rust, so a game was devised to rid the corrosion from the article. Sand and vinegar were placed in a bag with the chainmail and it was tossed back and forth between the soldiers. This protection was insufficient to protect from the sword, lance, flail, mace and axe. Later in the century a chainmail coif was developed to protect the head.
Chainmail armor was used by the last of the Romans, and by some of the invading Germanic tribes, including the Goths. Chainmail armor kept its popularity among the nobility of medieval Europe until, in the 13th century, plate armor began to be used instead, providing greater protection. This change was due to the fact, that the sharp tip of a sword or an arrow could pass through the chainmail.
Helmets also evolved from simple designs to large metal buckets, after which became large sculptured pieces to deflect arrows. Subsequently, helmets were assembled to the rest of the armor.
Full Armor, which could weigh up to 30 kilo, appeared in the 14th century. The armor plates were well designed, and the Knights could still keep a surprising agility. If a Knight with armour fell from the horse, he could easily get up without help. There are anecdotes and descriptions of warriors that wearing a suit of armor made the pine and other exercises in moments of calm.
Armatures put greater emphasis on deflecting projectiles and strengthening the areas most exposed to blows. Later appeared more elaborate models of armor plates with engravings, which were more ceremonial and prestigious than practical.
The armor represented a high cost to the Knight, because he would have to pay for their own equipment and his Squire.
Armor manufacture was a profitable business, and even second-hand armor would take a large part in the Medieval market. During battles, the troops of the victorious side could seize large sums of money stripping and taking armor of the dead Knights.