You start off with apprx. 15 peasants to build a town hall. this town hall provides shelter for all units and creates more peasants. u then have the peasants build barracks (also provides shelter for all units),stable,blacksmith,storehouse,library,walls,etc. the peasants also gather food (after building mill),stones,and wood to bring back to townhalls or storehouses. peasants also build mines over coal,gold,and iron resources and u place certain amnt of peasants in them (u can upgrade mines too to put more peasants in). i think 8000 units (soldiers,peasants,etc)can be created. (EVEN more with new add-on and american conquest game). Map is by far larger than any civ map. the graphics are so intense u can see the wheat sway to the wind where the peasnats gather food.
all units,techs,buildings,upgrades,etc require a mix of some resources to build.
barracks-create units,drummer,and officer that leads formation groups (group of 15,36,72,120). u also improve unit offensive/defensive points (upgrades).
stables-build calvary,dragoons, etc and make upgrades here.
library-improve food production,ship building,stone production,gunpowder,etc.
common strategy is to build more than one townhall (to keep producing peasants),more than one barrack,stable,artillary depot,etc. this way, you can have all buildings pumping out units at the same time.
i was never into 17th/18th cent. strategy games (or any strat games that are not civ) but this one blew me away.
feel free to ask me any other questions about cossacks.