The son of a priest, Nikolai Fedotovich began his studies first in law in Kiev, where he came under the spell of B. V. Antonovich and turned his attention to archeology. After a brief stint in the Kiev courts in 1891, he moved to Moscow where he worked in the archives of the Ministry of Justice and then to state archives in Warsaw. Returning to Kiev and teaching at the Polytechnic Institute, he joined the editorial board of “Kievskaia starina” and became particularly active in museum work. In 1899 in concert with the convocation of the 11th Archeological Congress in Kiev Beliashevskii helped to build the Kiev Museum of Art and Science. Elected to the First State Duma from Kiev Province in 1906, he helped to organize the Kiev Society for the Protection of Monuments of the Ancient and the Arts in 1910; in 1918 he wrote the first Law of the Ukrainian Republic on the protection of monuments of history, culture and art and was active in the All-Ukrainian Committee for the Protection of Antiquities and Art in Ukraine. During the Great War, the Academy of Sciences dispatched him to Galicia and the Bukovina to protect the archeological finds behind the military front.