Catherine the Great is a purposed-designed solitaire wargame of the expansion of the Russian Empire under Empress Catherine II (1762-96). The player purposefully conducts the affairs of the Russian Empire and its allies, while the game system does the same for the anti-Russian coalition made up of a shifting alliance of powers.

Central to play of the game are its 'policy cards.' They trigger various strategies, powers at war, and other events that shape the general course of play. Policy cards are activated in one of two ways: the Empire player can choose which policies he will activate, while coalition policies are activated by the draw of markers. The Empire player may move his forces freely. The game system moves coalition forces according to a schedule of precedence.

The objective of the game is for the Russian Empire to have gained an advantageous position at the end of play, measured in terms of gaining certain objectives. The player must, however, also look toward maintaining the "balance of power," or he may face disintegration of the entire European state system. Depending on how well the player attains his objectives, then, will really be the thing that determines the nature of victory.

While Catherine the Great has been purpose-designed to be a solitaire game, more than one can play at the same time as part of a Russian Empire command team. Player's can divvy up responsibilities as they please for different parts of the Russian Empire, with the most veteran gamer taking the role of Czar and deciding who gets what resources.

Each region represents a distinct geographic area or province within a power. Each unit represents an entire army or fleet. Each turn represents five years.