Following the Confederate purchase of Sonora and Chihuahua, which extends the CSA–USA border and gives the Confederates the Pacific port of Guaymas, the United States declares war on the Confederacy. Early on in the war, Confederate troops under Jeb Stuart capture a large quantity of gold and silver ore from a Union mining town after successfully occupying the newly purchased provinces. Meanwhile, a Union cavalry colonel, George Armstrong Custer, successfully uses Gatling guns against Kiowa Indians and Confederate cavalry in Kansas. Soon, the United Kingdom and France, both Confederate allies, blockade and bombard US port cities such as Boston and New York, along with those on the Great Lakes.