Humans are summoned using the trap command for an area. Higher tier humans can be summoned using Lures. Higher tiers come with additional followers. It is important to note that a follower will also bring any of its followers. So a Warrior will bring peasants. A Knight will bring Warriors, and then the warrior will bring its peasants as well.
Humans are divided into tiers. There are a few units that do not fit will into any tier.
Tier 1: (everyone in tier 1 comes alone, they are summoned with a "Gold" trap)
Countrywoman
Huntress
Peasant
Hunter
Tier-less:
Prostitute (comes alone, but needs a lure)
Maid and Servant (only comes with knights ladies and Lords)
Priest and Priestess (Only come with Lord Parties)
Tier 3:
Sorcerer and Sorceress
Lady
Knight
Tier 4:
Lord
Prostitute:
For additional information: Prostitute