The John Jung Letters consist mainly of 25 letters from Jung to Fanny (Boulden) Peterson, 1929-1936. The letters reveal Jung's adjustment to and reflections on life in the United States, as well as his common daily activities and his experiences in the American educational system. As indicated by Fanny Peterson in 1984, "his intriguing letters are a literary event, I feel. They reveal a developing personality and a young man dedicated to making it in a 'white man's world'.” (see folder 27)

Also included is one letter from Nelson Sawvain, former Superintendent of Schools in Devils Lake, to Jung; a story written by Jung after he had been in Boulden’s class for eight weeks; a biographical account about Jung written by Carol Welte; and photocopied materials from the archives at Purdue University.