 He was brevetted several times.When the Spanish–American War erupted, Lt. Col. Schwan was appointed brigadier general of volunteers and colonel in the Regular Army in May 1898, making him one of the only foreign-born generals in the Spanish–American War.He assumed command of the First Division of the Fourth Army Corps, which had mustered in at Mobile, Alabama before moving to the Tampa assembly area in early June and Miami, Florida on June 20.