The John Jay Stevens Diaries consist of two diaries written by Stevens between September 4, 1863 and October 31, 1863 while commissary officer of the 110th New York Infantry Regiment during the American Civil War. Diary one entries commence as the 110th embarked on its cruise from New Orleans, La. to what would be known as the Battle of Sabine Pass, Texas at the mouth of the Sabine River. Stevens details eight days aboard the troop transport steamer 'Thomas Winthrop' in the Gulf of Mexico covering the battle of and the Federal retreat from Sabine Pass and the return trip to New Orleans. From September 12, 1863 through the end of the second diary he covers the 110th N.Y.'s overland campaign in Louisiana. Diary Two begins on September 26, 1863. The body of the entries after the cruise include troop movements, day to day camp life, and the Battle of Carrion Crow Bayou. Stevens documents experiences in and scenery of the Louisiana bayou country with vivid description. Entries are penned from New Orleans, Algiers, Brashear City, Berwick, Camp Bisland, Franklin, New Iberia, camp on the Teche, and Opelousas. He touches on foraging expeditions to abandoned plantations, the reaction of the local populace to the presence of the Federal troops, race relations and slavery, the landscape and weather, the character of the army and his commanding officers, death and disease, and his relations within the ranks. Stevens writes with a range of tones, but mantains a sense of humor throughout. This collection also includes a fascinating letter written by Stevens in 1875 while he was living in Greeley, Colorado. The letter, written to his sister Kate Forbes and her family in Oswego, New York, reports on the town and his life there. From the letter we learn that Stevens had ventured west for, among other reasons, his health. The collection also includes a letter fragment of an unknown child relative of Stevens in Cheyenne, Wyoming.