The monograph, written on a wide and diverse source basis, is devoted to a little-known page in the history of Russia of the 20th century: the system of parliamentarism formed by the Cossacks of the Kuban during the Civil War, and its functioning. It first examines the prerequisites for the formation of an independent Cossack republic in the Kuban in 1917-1920, the principles of organization of state power, the place and role of the Kuban Cossacks in the creation of the Southeast Union, reveals their attempts to preserve the Russian Empire, transforming it into a territorial federation with a republican form of government. A significant place was given to the problem of the constitutional and legal status of the Kuban after the establishment of Soviet power in the region in the spring of 1918, whose supporters pursued a policy of decay.