Even in random games it is important to have some elements of plot or other narrative to help get the player into the game.
Opening dialogue
Each pre-defined side should have a set of positive and negative statements about them. For example, the positive statement for the side "UN" might be "to unite the world", and a negative statement for the side "the facists" might be "oppress their people and commit genocide against races they consider inferior".
The starting message for the UN player would then be: "We must unite the world, and rid it of the facists, who oppress their people and commit genocide against races they consider inferior". This gives the player a reason to win.
Events dialogue
Events dialogue would condense the game's events to a headline, using standard formats:
After [heavy fighting/scant resistance], the [demonyn] city of [city name] [falls to/is occupied by/is captured by/is liberated by] the [demonyn] [unit name].
After [heavy fighting/scant resistance], the [demonyn] [unit name] [enters/marches into/captures/occupies/liberates] the [demonym] city of [city name].