The spread of baseball during the mid-nineteenth century is sometimes associated with soldiers and former soldiers who served during the US Civil War. This association is partly true in Colorado, Kansas, and Nebraska. However, white settlers from the Northeast and Midwest also brought baseball and similar ball games to the region before the Civil War began, and civilians played ball throughout the war. The first team organized in the region was the Denver Base Ball Club in March 1862, although the team disbanded as warmer weather permitted mining activity to resume. Increasing numbers of baseball clubs were organized in Colorado, Kansas, and Nebraska soon after the war ended, and tournaments were held for the championship of each state or territory by 1871. The Otoe BBC of Nebraska City and the Omaha BBC also hosted the first professional baseball team, the Cincinnati Red Stockings, in 1869. These and other aspects of baseball as it took root in Kansas, Colorado, and Nebraska are recounted.