The collection includes correspondence, manuscripts, memoirs, diaries, notes, subject files, documents, photographs, and printed materials. Most of the material in the collection concerns Nikolaev's tenure as military attachʹe at the Russian embassy in Washington. Cataloged correspondents include Mikhail T. Florinsky and Geroid T. Robinson. There is a typescript by Vasiliĭ O. Kli︠u︡chevskiĭ, "Kratkoe posobie po russkoĭ istorii." Among the correspondence are cablegrams and official communications to the Russian embassy during World War I and the revolutionary period. Manuscripts, mostly by Nikolaev, concern contemporary and historical military topics. Diaries and memoirs deal with Nikolaev's travels to Europe during World War I and his activities as military attachʹe. Among orders granted to Nikolaev is the "Order of the Sacred Treasure," signed and sealed by the Japanese Emperor Meiji (1911). Printed materials include many articles by Nikolaev.

The papers consist of correspondence, manuscripts, notes, documents, photographs, subject files, and printed materials. Among the correspondents are Louis Marin, Mikhail Osorgin, Alekseĭ Remizov, Boris Ubegaun, George Vernadsky, and the "Eurasianists" Petr Savitskiĭ and Petr Suvchinskiĭ; there is one letter from Nikolaĭ Marr. There is the manuscript of Nikitin's memoirs, "Arabeski: pochemu i︠a︡ stal vostochnikom?" There are extensive notes of lectures by Nikolaĭ Berdi︠a︡ev in 1925. Numerous photographs date from Nikitin's service in Iran. Subject files concern the Eurasian movement (evraziĭstvo), and the Committee "For Return to the Homeland" ("Za Vozvrashchenie na Rodinu"). Printed materials largely consist of Nikitin's own writings.