This collection contains the diary of John H. Hancock, who served in Company H, 29th Massachusetts Infantry of the Union Army during the American Civil War. The diary entries cover January-June 1862, with a single entry made from Paris, Kentucky on April 1, 1863. Hancock's diary entries relate largely routine information such as weather conditions, personal health, camp routines, and troop movements. Longer entries relate to orders, marching, battles, and war news. Frequent mentions are made of gun boats. Contrabands and prisoners of war are also mentioned, as are activities of other regiments within the brigade.