The congress was opened by the "All–Union Headman" Mikhail Kalinin, who in his opening speech called the proletarian Paris Commune the historical predecessor of the Soviet State. "The victory of the Great October Socialist Revolution found its legal expression in the Constitution of the Russian Socialist Federative Soviet Republic, adopted by the Fifth All–Russian Congress of Soviets in 1918, which included the "Declaration of the Rights of the Working and Exploited People". The victorious proletariat in alliance with the poorest peasantry formalized its dictatorship by law, the task of which was to abolish the exploitation of man by man and divide society into classes, to ruthlessly suppress the exploiters and establish a socialist organization of society", said Kalinin. The first constitution of the Soviet Union in 1922 marked the formation of a new state that united the peoples, but it could not reflect the gains of socialism, which should be done by the adoption of a new constitution.