From the Developer's web site:

What is so special about Cossacks - European Wars ?

Endless fun by a range of long campaigns and extra scenarios. A true 3D-modelled landscape, that seriously affects tactics and strategies. No less than 16 nations with their unique architectural styles, technologies and units. Not to forget titanic battles with up to 8000 units on one map. The economy system is complex but easy to handle and provides increased game balance, e.g. when iron and coal are used up as ammunition by artillery and warships. Civilian buildings and units can be taken over, so that a fierce guerillia war can be led behind the enemy borders for the first time.

From the contributor:

Cossacks - European Wars is a game for the serious RTS player and history buff. It can be incredibly challenging at times, but always impressive and engrossing.