Medieval Infantry
When people think about Medieval Warfare, what comes to mind first are Knights, and fair's fair they were important and would be honed to a fine edge. However they were only part of the equation. Here's a rough guide to Medieval Infantry.
Note
This is a fairly big complex thing with a lot of local details and variation, since it covers a lot of Europe between roughly 500 to 1500.
Levies
Peasants put under arms. A medieval lord could raise a levy in times of war, gathering up young men from the farms working his lands. Usually they'd be given at least a helmet and a basic weapon and possibly some armour and some insignia to mark themselves out, but bringing your own stuff was highly encouraged. They'd get a bit of training and would then be sent off to war and if things went well, they'd go back to their fields with a bit of loot.
The advantage of this system is that it was fairly cheap and simple to set up. Of course it had big disadvantages. First of all, a force of farmers with minimal training and basic equipment is not a formidable force unless you have a lot of these guys. Second a peasant under arms is not one tending the crops and paying rent, especially if he ends up dead. This limits when you can raise a levy (IE not during sowing or harvesting), how long you can keep it under arms and how many of these guys you recruit.
Urban Militias
Similar to levies, but in towns and cities. Also often better equipped as cities were usually richer per-capita.
Yeoman
Unlike serfs or tenants, yeomen owned a plot of land as their own. This meant they had more income than Paul the Peasant but they were also required to use some of that money to buy gear and serve as soldiers.
Sergeants
Full time warriors retained by a noble. A lordling will find a big strong guy from his peasants and tell him that he has a job for him. He gets more training than a levy does, a regular wage and room and board as well as better arms and armour. In peace, having a big strong dude who's good in a fight and owes everything to you is a good asset to have, and he can train up levies in times of war. In times of war, these guys can be your heavy infantry.
Mercenaries
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