http://www.gog.com/gamecard/knights_and_merchants_the_peasants_rebellion

What's cool about it:
Includes the original Knights & Merchants: The Shattered Kingdom and the expansion The Peasants Rebellion
Complex ΓÇ£daily lifeΓÇ¥ economy and resource management
No population cap - the size of your army depends only on your capacity to feed your soldiers
Overview:
After many battles, a former kingdom has been divided into many small principalities and earldoms. The king's troops were pushed back into one last royal province, and the rulers of the other provinces waged terrible, destructive wars against one another. The whole land fell into a state of chaos and now the former royal capital itself is under siege by the armies of the rebel lords. You belong to the last remaining group of loyalists, and have been commanded to go to the king in light of the imminent attack.

A conspiracy against the king catapults the captain into a situation where he finds himself responsible for the defence of the last royal province. This is all that remains of the shattered kingdom, which has been torn apart by rivaling lords. And now even the king himself, ensconced in his capital, is threatened by enemy armies. This is the starting point of your Middle Ages adventure. Now you must win back all those provinces which once belonged to your king.