_Aggression: Reign over Europe_ uses an unusual scenario for strategy games:
it covers both World Wars and is set between 1910 and 1950. The player takes
the role of either Germany, Britain, Russia or France during the four
campaigns. Most of the time is spent on the European map where the player
takes care of the military and economic development of his nations, e.g. with
diplomacy or trading. This part is played in real-time but can be paused at
any time.

Since the goal is gain reign over Europe there are also a lot of battles to be
fought. The player can either let them calculate them or participate in them
in real-time tactics battles. Like in similar games the players manages big
armies and can use several tactics, e.g. flanking the enemy. Important to note
is that there are about 150 different units but no naval ones. There are also
six scenarios with single battles.