A strategy game is a type of game in which the players’ unconstrained, and frequently autonomous, decision-making abilities play an important role in determining the outcome. Internal decision tree thinking is almost necessary for all strategy games, and good situational awareness is required.
Strategy games are seen as a descendent of war games, and strategy is defined in terms of the context of warfare, but this is only part. A strategy game is one that relies primarily on strategic thinking, and when it comes to defining what strategy is, two things must be considered: its degree of complexity and the scale of game actions like those seen in a Total War series.
A strategy game in its cultural context is any game that belongs to a tradition dating back to war games, has more strategy than the usual video game, incorporates gameplay conventions, and is played by a specific community. Although war is prominent in strategy games, it isn’t the whole picture.