All the AGEOD games are very good. This one covers the 7-years war in Europe, and comes with several long and short campaigns. The game works on a WEGO system, and focuses on operational level warfare. Supply is very important, as are weather conditions.
You can build units for your armies, give orders to your generals (which they will not always carry out, due to an activation system, simulating the difficulties in co-ordinating actions in this period). There is no 3-d battle function. Strictly old fashioned strategy, played out on a beautiful 2-d map. The units and leaders also have very nice art to represent them.
Highly recommended, in-depth simulation of the campaigns of the 7-years war in Europe!