Storm Across Europe is a turn based strategy game, depicting the entire European Theatre, from the southern parts of Norwegen, Sweden and Finland till North Africa, from Great Britain and Tunesia till the Middle East and deep into Russia (the Ural) and the seas and oceans from the eastern Atlantic till the Black Sea and Persian Gulf.
The game was originally released for the Commodore 64 and later transported to the Amiga and DOS.
The map covers 224 areas and 37 different countries. Each turn is 3 months realtime. The player can choose to play Germany, or, in hotseat mode Germany, the Soviet Union or the W-Allies (the Allies can be played by the computer, Germany cannot). The game has 6 historical starting points (scenarios) ranging from Autumn 1939 till Summer 1944. The game also includes a scenario builder.
The player has to command his land, air and naval units (which are divided in over 10 different typer, like tank armies, infantery armies, mechanized/ painf armies etc.On top of that, he has to manage his production, to build new units. Areas have both terrain (affecting combat) as well as different production values. The game also features some research options, so even the V1 and atomic bomb can be pursued.
According to Wikipedia (1) Storm Across Europe was the first computer game to try to cover WW-2 on a grand strategic scale (quite a feat for a 64 kilobyte computer) and as such "could be seen as the grandfather of games that improved and refined the concept like Clash of Steel and the Hearts of Iron series".
(1) Source: Wikipedia, "Storm Across Europe", available under the CC-BY-SA License.