The author analyses how external circumstances affected Marxist historical science, which was definitive in shaping Soviet ideology during the period of new economic policy. Further, the ideas that were drawn from various sources, including both those that Bolshevik scholars got acquainted with in emigration and those translated and published in the USSR during the 1920s, are highlighted. The author focuses on the evolution of the views of M. N. Pokrovsky, the leading Marxist authority on the history of the First World War at the time.