The regiment was attached to Grover's Division, Department of the Gulf, to January 1863.

3rd Brigade, 4th Division, XIX Corps, Department of the Gulf, to August 1863.

2nd Brigade, Grover's Division, District of Savannah, Georgia, Department of the South, to March 1865.

The 159th New York Infantry mustered out of service October 23, 1865 at Augusta, Georgia.

Occupation of Baton Rouge, Louisiana, December 17, 1862, and duty there until March 1863.

Expedition to Franklin and Opelousas, Bayou Teche Campaign, April 11–20.

Moved to New Orleans, Louisiana, then to Fort Monroe and Bermuda Hundred, Virginia, July 17–25.

Sheridan's Shenandoah Valley Campaign August 7 – November 28.

Moved to Goldsboro, North Carolina, April 8; then to Savannah, Georgia, May 2.