Undated photograph of an unidentified Union engineer, holding a civilian hat with the engineer “castle” insignia.

Engineers played a vital role in the Civil War, building pontoon and railroad bridges, forts, emplacements for artillery batteries and roads.

Perhaps the most famous engineer unit from the Trans-Mississippi Theater was Colonel Josiah W. Bissell’s “Engineer Regiment of the West,” which was mustered into service in the fall of 1861. The regiment contained men from Missouri, Illinois, Michigan, and Iowa. Bissell’s Engineers contributed to Union battlefield victories early in the war, such as New Madrid, Island No. 10, and Corinth. They repaired and built railroads and bridges in Tennessee and Mississippi through the rest of 1862 and 1863. In early 1864 Bissell’s Engineer Regiment was consolidated with the 25th Missouri Infantry to form the 1st Missouri Engineers. The regiment took part in the Atlanta campaign, Sherman’s “March to the Sea”, and the Carolinas campaign.

Carte-de-Visite by Hamill’s Photographic Gallery, Monmouth, Ill.

Image Courtesy Wilson’s Creek National Battlefield; WICR 31528