Richard Owen was still engaged on his report of the state geological survey for the years 1859-1860, (published in 1862) when he was offered by governor O.P. Morton the Lt. Colonelcy of the 15th (Indiana Volunteers) and accepted; reading the proof of his report, in camp, May 1861. After the battle of Greenbrier, (West Virginia), Dr. Owen was promoted colonel of the 60th (Indiana Volunteers)...and remained with this regiment until Dec. 1863, participating in the capture of Vicksburg and Jackson, (Mississippi) and in the Red River campaign.