During the American Civil War there were a variety of saddles in use by the Federal Cavalry. The 1859 McClellan, however, was by far the most common saddle used by Union horse soldiers. Six years before the Civil War, then Captain George Brinton McClellan served as a member of a military commission to study European military tactics, weapons, and logistics. While in Europe, McClellan observed battles during the Crimean War, focusing on the organization of Engineer and Cavalry forces. On his return to the United States, McClellan proposed a cavalry manual adapted from the Russian Cavalry. He also developed a cavalry saddle which was a modification of a Hungarian model used in the Prussian service and included features found in Mexican and Texan saddles as well as characteristics of the Hope, Campbell, and Grimsley saddles. Under Secretary of War (and future President of the Confederacy) Jefferson Davis, the Army conducted field trials to determine the most practical and efficient equipment for the Cavalry and Dragoons. In addition to the new saddle developed by McClellan, a number of other styles were considered including the standard service Grimsley, the Hope, Campbell, and a Jones "adjustable tree" saddle.