The Russia/Commonwealth of Independent States (CIS) Collection emphasizes the twentieth century, though some materials from the latter half of the nineteenth century also form part of the collection. In accordance with the Hoover Institution's dedication to the study of war, revolution and peace, the collection is concerned primarily with the history, ideology, politics and international relations of Russia and the former Soviet Union. There are also holdings related to economics, demography, and law. This collection is one of the most outstanding features of the Hoover Institution. Few libraries in the world can match its depth or quality. It encompasses writings on Imperial Russia after 1861, the period of the Provisional Government of 1917, the Bolshevik Revolution, the Civil War, the Soviet period, and contemporary events.