12th Missouri Volunteer Infantry The 2nd Missouri Volunteer Infantry was an infantry regiment that served in the Union Army during the American Civil War . The regiment was organized by Colonel Peter J . Osterhaus , a veteran of the respected 2nd Missouri Volunteer Infantry ( 3 months , 1861 ) . The majority of the soldiers in the 12th were ethnic Germans . This intermixed German - American unit also had a large portion of its ranks filled by volunteers from Illinois . Service . Organized at St . Louis , Missouri , August 1861 . < br > Attached to Fremont ' s Army of the West to January 1862 . < br > 2nd Brigade , Army of Southwest Missouri , to February 1862 . < br > 2nd Brigade , 1st Division , Army of Southwest Missouri , to May 1862 . < br > 3rd Division , Army of Southwest Missouri , to July 1862 . < br > District of Eastern Arkansas , Dept . of Missouri , to December 1862 . < br > 1st Brigade , 11th Division , Right Wing 13th Army Corps ( Old ) , Dept . of the Tennessee , to December 1862 . < br > 2nd Brigade , 4th Division , Sherman ' s Yazoo Expedition , to January 1863 . < br > 2nd Brigade , 1st Division , to September 1863 . < br > 1st Brigade , 1st Division , 15th Army Corps , to December 1863 . < br > 3rd Brigade , 1st Division , 15th Army Corps , to November 1864 . Detailed service . Fremont ' s advance on Springfield , Missouri , September to November 1861 . Moved to Jefferson City , thence to Sedalia and Springfield . < br > To Wilson ' s Creek October 6 – 8 . Duty at Rolla until January , 1862 < br > Expedition to Danville December 26 , 1861 . < br > Curtis ' Campaign in Missouri and Arkansas against Price January to March 1862 . < br > Advance on Springfield February 2 – 16 . < br > Pursuit of Price into Arkansas February 14 – 29 . < br > Battles of Pea Ridge , Arkansas , March 6 – 8 . < br > March to Batesville April 5 - May 3 ; thence to Helena , Arkansas , May 25 - July 14 . < br > Expedition from Helena to mouth of White River August 5 – 8 . < br > Moved to Ironton - Pilot Knob , Missouri , September 1 . < br > To St . Genevieve November 12 , and return to Helena November 23 . < br > Sherman ' s Yazoo Expedition December 22 , 1862 , to January 3 , 1863 . < br > Chickasaw Bayou December 26 – 28 . < br > Chickasaw Bluff December 29 . < br > Expedition to Arkansas Post , Arkansas , January 3 – 10 , 1863 . < br > Assault and capture of Fort Hindman , Arkansas Post , January 10 – 11 . < br > Moved to Young ' s Point , La . , January 17 – 23 . Duty there until March and at Milliken ' s Bend until April . < br > Expedition to Greenville , Black Bayou and Deer Creek April 2 – 14 . < br > Demonstration on Haines and Drumgould ' s Bluffs April 29 - May 2 . < br > Moved to join army in rear of Vicksburg , Mississippi , via Richmond and Grand Gulf May 2 – 14 . < br > Mississippi Springs May 12 – 13 . < br > Jackson May 14 . Siege of Vicksburg , Mississippi , May 18 - July 4 . < br > Assaults on Vicksburg May 19 and 22 . Advance on Jackson , Mississippi , July 4 – 10 . < br > Siege of Jackson July 10 – 17 . < br > Bolton ' s Depot July 16 . < br > Brier Creek , near Canton , July 17 , Clinton July 18 . < br > Camp at Big Black until September 27 . < br > Moved to Memphis , Tennessee , thence march to Chattanooga , Tennessee , September 27 - November 21 . < br > Operations on Memphis & Charleston Railroad in Alabama October 20 – 29 . < br > Cherokee Station October 21 and 29 . < br > Cane Creek October 26 . Tuscumbia October 26 – 27 . < br > Battles of Chattanooga November 23 – 27 . < br > Lookout Mountain November 23 – 24 . < br > Mission Ridge November 25 . < br > Ringgold Gap , Taylor ' s Ridge , November 27 . < br > March to relief of Knoxville , November 28 - December 8 . < br > Garrison duty in Alabama at Woodville and Scottsboro , Alabama , and at Cleveland , Tennessee , to May 1864 . < br > Atlanta ( Georgia ) Campaign May 1 to September 8 . < br > Demonstration on Resaca May 8 – 13 . < br > Battle of Resaca May 13 – 15 . < br > Advance on Dallas May 18 – 25 . < br > Battles about Dallas , New Hope Church and Allatoona Hills May 25 - June 5 . < br > Operations about Marietta and against Kenesaw Mountain June 10 - July 2 . < br > Bushy Mountain June 15 – 17 . < br > Assault on Kenesaw June 27 . < br > Nickajack Creek July 2 – 5 . < br > Chattahoochie River July 6 – 17 . < br > Battle of Atlanta July 22 . < br > Siege of Atlanta July 22 - August 25 . < br > Ezra Chapel , Hood ' s 2nd Sortie , July 28 . < br > Flank movement on Jonesboro August 25 – 30 . < br > Lovejoy Station September 2 – 6 . < br > Pursuit of Hood into Alabama October 1 – 21 . < br > Mustered out by Companies from August 12 to November 14 , 1864 . < br > Consolidated with Detachments from 3rd and 17th Missouri Volunteer Infantry and subsequently transferred to 15th Missouri Infantry . Casualties . The regiment lost during service 10 officers and 102 enlisted men killed and mortally wounded and 2 officers and 94 enlisted men by disease . Total 208 .