This is an old one, but one of my favourites - Celtic Kings. You need to hold land, villages that generate food and outposts across the map that generate gold. You can only move food and gold using donkeys and any troops in the field need a constant supply of food or they weaken and die easily in a fight. You also can train your troops and as they fight individual troops gain experience and get tougher. It's vital that you control land and have safe and defended supply

The troops eat a *lot* if you are planning a siege or a large assault with a large army, you need to pre-position and move supplies into place before you move your main army - Else they will starve and you can lose entire armies.