Bernard John Dowling Irwin and the development of the field hospital at Shiloh.

The field hospital remains a centerpiece of casualty care evacuation systems, dating back to the Civil War. Dr. Bernard John Dowling Irwin is credited with establishing the first tent field hospital during the battle of Shiloh. However, controversy regarding this claim exists because of the confusing practice of using the term "field hospital" to refer to facilities with different capabilities. By examining the specific levels of care available on the battlefield, I review the evolution of the different types of field hospitals, focusing on the increasingly complex capabilities that evolved in the spring of 1862 in the Western Theater. I conclude that Irwin's hospital was the first practical demonstration that sufficient inpatient care could be provided on the battlefield, eliminating the need to evacuate unstable patients.