Organized at Hamilton, Ohio, and mustered in September 20, 1861. Moved to Covington, Ky., September 26. Assigned to guard duty along the Kentucky Central Railroad, Headquarters at Cynthiana, till November. At Paris, Ky., till December. Attached to 3rd Brigade, Army of the Ohio, November-December, 1861. 3rd Brigade, 1st Division, Army of the Ohio, to September, 1862. 3rd Brigade, 1st Division, 3rd Corps, Army of the Ohio, to November, 1862. 3rd Brigade, 3rd Division, Centre 14th Army Corps, Army of the Cumberland, to January, 1863. 3rd Brigade, 3rd Division, 14th Army Corps, Army of the Cumberland, to October, 1863. 2nd Brigade, 3rd Division, 14th Army Corps, to August, 1864.Operations about Mill Springs and Somerset, Ky., December 1-13, 1861. Action at Fishing Creek, near Somerset, December 8. Advance to Camp Hamilton January 1-17, 1862. Battle of Mill Springs January 19-20. March to Louisville, Ky., thence moved to Nashville, Tenn., via Ohio and Cumberland Rivers February 10-March 2. Marcia to Savannah, Tenn., March 20-April 8. Advance on and siege of Corinth, Miss., April 29-May 30. Pursuit to Booneville May 31-June 14. Moved to Tuscumbia, Ala., June 22, and duty there till July 27. Moved to Dechard, Tenn., July 27. March to Louisville, Ky., in pursuit of Bragg August 21-September 26. Pursuit of Bragg into Kentucky October 1-15. Battle of Perryville, Ky., October 8 (Reserve). March to Nashville, Tenn., October 16-November 7. Duty at South Tunnel, opening railroad communications with Nashville, November 8-26. Guarding fords of the Cumberland till January 14, 1863. Duty at Nashville, Tenn., January 15-March 6. Moved to Triune March 6, and duty there till June. Expedition toward Columbia March 6-14. Franklin June 4-5. Middle Tennessee or Tullahoma Campaign June 23-July 7. Hoover's Gap June 24-26. Occupation of Middle Tennessee till August 16. Passage of the Cumberland Mountains and Tennessee River, and Chickamauga (Ga.) Campaign August 16-September 22. Battle of Chickamauga September 19-21. Siege of Chattanooga, Tenn., September 24-November 23. Demonstration on Dalton, Ga., February 22-27, 1864. Tunnel Hill, Buzzard's Roost Gap and Rocky Faced Ridge February 23-25. Reconnoissance from Ringgold toward Tunnel Hill April 29. Atlanta (Ga.) Campaign May 1-August 3. Demonstration on Rocky Faced Ridge May 8-11. Battle of Resaca May 14-15. Advance on Dallas May 18-25. Operations on Pumpkin Vine Creek and battles about Dallas, New Hope Church and Allatoona Hills May 25-June 5. Operations about Marietta and against Kenesaw Mountain June 10-July 2. Pine Hill June 11-14. Lost Mountain June 15-17. Assault on Kenesaw June 27. Ruff's Station July 4. Chattahoochie River July 5-17. Peach Tree Creek July 19-20. Siege of Atlanta July 22-August 3. Ordered to Chattanooga, Tenn., August 3. Mustered out August 26-September 28, 1864, expiration of term. Veterans and Recruits transferred to 18th Ohio Infantry (Reorganized).Regiment lost during service 5 Officers and 75 Enlisted men killed and mortally wounded and 2 Officers and 126 Enlisted men by disease. Total 208.