The majority of the more than 600,000 soldiers who perished during the Civil War were victims of disease rather than bullets. The Union’s prewar medical establishment was too small to handle wartime demands and the Confederacy started from scratch. Both sides struggled throughout the conflict to provide competent medical care, and but for the assistance of civilian volunteers the soldiers’ suffering would have been far greater. Although the Confederacy established major medical facilities in the Eastern Theater, it failed to do so in the Trans-Mississippi. The Union, however, developed medical care west of the Mississippi that fully matched its accomplishments elsewhere. St. Louis emerged as one of the most important regional medical centers, accommodating military patients throughout the Mississippi River valley. Indeed, though primitive in some aspects when compared to today, the medical treatment available to Union soldiers in the Trans-Mississippi was the finest soldiers had every received up to that point in history.