Fort Sumter is a two-player Card Driven Game (CDG) portraying the 1860 secession crisis that led to the bombardment of Fort Sumter and the American Civil War. The game pits a Unionist versus a Secessionist player. Each player uses the area control mechanic pioneered in the We The People design and immortalized in Twilight Struggle to place, move, and remove political capital. The location of political capital determines who controls each of the four crisis dimensions (Political, Secession, Public Opinion, and Armaments). After three rounds of play, the game culminates in a Final Crisis confrontation to determine the winner.

The heart of the Fort Sumter design is the CDG system in which players use Strategy cards for their value or historic event to acquire political capital from the crisis track. Political capital tokens are used to compete for control of the twelve map spaces. Here the likes of William Lloyd Garrison, Sam Houston, Jefferson Davis, and Harriet Beecher Stowe walk on stage, while the Southern states dissolve the Union.