Series I contains the earliest material in the collection and is mostly correspondence. The bulk of the series spans the years 1900-1940, covering Courant's time as a young student to his immigration to the U.S., but also includes files from around the time of his death. The series contains materials on Courant's schooling in Germany, including diplomas, certificates and records of his coursework as well as documents from his time in the German Army during World War I. These include trench maps and a certificate for a war service medal. Much of the series consists of correspondence with colleagues at the University of Gt̲tingen, their articles and dissertations. The letters pertain to mathematics at Gt̲tingen, the affects of the Nazi regime on academia and mathematics and other personal matters. Courant's move from Germany to the U.S. is also documented in this series. Some material in Series I was used by Courant biographer Constance Reid. This is indicated by folder-level notes. Series II, which contains a wide range of material, represents the bulk of the collection. It is largely comprised of correspondence with American, German and international colleagues, many of whom Courant tried to help secure relocation and employment at various U.S. universities during the Nazi era. Correspondence is typically filed under the correspondent's name or by the first letter of the surname. Many of Courant's publications, lecture material and articles are also scattered throughout this series. Material related to his book publishing, translation, rights and written critiques from readers and mathematicians are included as well. Publisher Springer-Verlag, and specifically Ferdinand Springer, figures prominently in this area. The collection details the full length of Courant's career at NYU. Administrative correspondence documents the growth of the Department of Mathematics and assembly of its faculty from Courant's closest colleagues and its evolution into the Institute for Mathematics and Mechanics and then into the Courant Institute of Mathematical Sciences. Courant and the IMS's World War II and post-war government consulting work is also well-represented in the collection, especially his work with the Atomic Energy Commission, the Office of Naval Research and IBM. Courant also spent the post-war period working to build a relationship between American and Soviet mathematicians and scientists. Correspondence and information about Soviet-American conferences are found in the collection as well. The material also reflects Courant's membership in the Mathematical Association of America, National Academy of Sciences, National Philosophical Society, Academy of Sciences of the U.S.S.R. and the Cosmos Club. The Courant Papers notably contains correspondence to and from Albert Einstein, Harald and Niels Bohr, Max Born, Fritz John, J.J. Stoker, K.O. Friedrichs, Abraham Flexner, Edward Teller and J. Robert Oppenheimer as well as many others.