The papers comprise correspondence, documents, institutional files, writings, lectures, memoirs, research notes, photographs, third party materials, printed materials, periodicals, microfilms, audio material, and digital files accrued by historian and professor emeritus of Columbia University, Leopold H. Haimson, during his professional life.

Correspondence, manuscripts, lectures, lecture notes, and subject files of Russian-American historian Mikhail Mikhailovich Karpovich (1888-1959). Karpovich was an employee of the embassy of the Russian Provisional Government in Washington, D.C., Professor Emeritus of Russian History and Literature at Harvard University, and founding editor of Novyĭ zhurnal.