Born in Sheffield, Massachusetts, on March 26, 1811, William Dewey entered the U.S. Military Academy at West Point from Clark County, Indiana in the summer of 1829. Dewey did not graduate from West Point. He was admitted to the Indiana bar about 1836, but left the legal profession to study medicine at the St. Louis Medical College and graduated about 1842. Dewey then settled in Wapello County, Iowa, and was living in Sidney, Fremont County, Iowa, when the Civil War began. He was appointed lieutenant colonel of the 15th Iowa Infantry on November 1, 1861, and was mustered into service on November 6, 1861.

The 15th moved to St. Louis, then was ordered to join Major General Ulysses S. Grant’s Army of the Tennessee. The regiment arrived at Pittsburg Landing, near Shiloh church, on the morning of April 6, 1862, just as Grant’s camps came under attack by General Albert Sidney Johnston’s Army of the Mississippi. The 15th hurried from the landing into action and fought for the remainder of the day. By the end of the battle, the 15th Iowa had lost nearly a quarter of its strength in killed, wounded and missing. Dewey was badly wounded in the shoulder and had his horse shot from under him.

Commissioned on August 1, 1862, Dewey was mustered in as colonel of the 23rd Iowa on September 19, 1862. The Iowa Adjutant General’s Report noted that the 23rd was “highly fortunate in the selection of its first field officers,” and was led by “officers who had won distinction and honor” in earlier actions.

Unfortunately, the 23rd lost many men to disease, including the 51-year-old Colonel Dewey, who, worn down by hardship and exposure, died of erysipelas on November 30, 1862, in the regimental hospital at Patterson, Wayne County, Missouri.

Dewey was not popular with his men at first, due to the fact that he was “strict and exacting in his discipline,” but quickly earned their respect. The Burlington Daily Hawk-Eye reported on December 13, 1862, that the field and line officers of the regiment had met and passed several resolutions, including “Resolved, That by Col. Dewey’s death we lose an able, energetic and accomplished officer, a brave and fearless commander, and a warm hearted generous friend.” Colonel Chester Harding, Jr., commander of the 2nd Division, Army of Southeast Missouri, served as a pallbearer and praised Dewey as “a thorough soldier, whose heart was in the cause which brings us to the field, and one upon whom we all relied to aid us when the hour of difficulty and danger had come,” and that Dewey’s “most anxious desire” was to give his regiment the training and discipline required to enable them to add to Iowa’s proud reputation.

Dewey is buried in the Woodland Cemetery in Des Moines, Iowa.

Carte-de-Visite by J.H. Emerson, Keokuk, Iowa.

Image Courtesy Wilson’s Creek National Battlefield; WICR 31870