Congress of Soviets of the Soviet Union in the context of "Congress of Soviets"

The Declaration and Treaty on the Formation of the Union of Soviet Socialist Republics (Russian: Декларация и договор об образовании Союза Советских Социалистических Республик) officially created the Union of Soviet Socialist Republics (USSR), commonly known as the Soviet Union. It de jure legalised a political union of several Soviet republics that had existed since 1919 and created a new federal government whose key functions were centralised in Moscow. Its legislative branch consisted of the Congress of Soviets of the Soviet Union and the Central Executive Committee of the Soviet Union (TsIK), while the Council of People's Commissars composed the executive.

The Treaty, along with the Declaration of the Creation of the USSR was approved on 30 December 1922 by a conference of delegations from the Russian SFSR, the Transcaucasian SFSR, the Ukrainian SSR and the Byelorussian SSR. The Treaty and the Declaration were confirmed by the First All-Union Congress of Soviets and signed by heads of delegations – Mikhail Kalinin, Mikhail Tskhakaya, and Grigory Petrovsky, Alexander Chervyakov respectively on December 30, 1922. The treaty provided flexibility to admit new members. Therefore, by 1940 the Soviet Union grew from the founding four (or six, depending on whether 1922 or 1940 definitions are applied) republics to 16 republics.

The Supreme Soviet of the Union of Soviet Socialist Republics (SSUSSR) was the highest organ of state authority of the Soviet Union from 1936 to 1991. Based on the principle of unified power, it was the only branch of government in the Soviet state, and headed the unified state apparatus.

Prior to 1936, the Congress of Soviets was the highest organ of state authority. During 1989–1991 a similar, but not identical organ acted as the highest organ of state authority. The Supreme Soviet appointed the Council of Ministers, the Supreme Court, and the Procurator General of the Soviet Union as well as elected the Presidium which served as the Soviet Union's collective head of state under both the 1936 and 1977 Soviet Constitutions.

The All-Russian Congress of Soviets evolved from 1917 to become the supreme governing body of the Russian Soviet Federative Socialist Republic from 1918 until 1936, effectively. The 1918 Constitution of the Russian SFSR mandated that Congress shall convene at least twice a year, with the duties of defining (and amending) the principles of the Soviet Constitution and ratifying peace treaties. The October Revolution ousted the provisional government of 1917, making the Congress of Soviets the sole, and supreme governing body. This Congress was not the same as the Congress of Soviets of the Soviet Union which governed the whole Soviet Union after its creation in 1922.

For the earlier portion of its life, the Congress was a democratic body. Over Russia there were hundreds of soviets, democratic local governing bodies in which the surrounding population could participate. The soviets elected the delegates to the Congress, and then in turn the Congress held the national authority, making the highest decisions. There were several political parties represented in the various sessions of the Congress, each of which fought for increasing their own influence in the soviets. However, as the Russian Civil War progressed, the soviets' authority was progressively reduced, with the rise of Stalinism effectively cementing this situation and decisively turning the Congress into a rubber stamp. The Congress was formed of representatives of city councils (1 delegate per 25,000 voters) and the congresses of the provincial (oblast) and autonomous republican councils (1 deputy for every 125,000 inhabitants).

The Constitution of the Soviet Union recognised the Presidium of the Supreme Soviet (between 1938 and 1989) and the earlier Central Executive Committee (CEC) of the Congress of Soviets (between 1922 and 1938) as the highest organs of state authority in the Union of Soviet Socialist Republics (USSR) between legislative sessions. Under the 1924, 1936 and 1977 Soviet Constitutions these bodies served as the collective head of state of the Soviet Union. The chairman of these bodies personally performed the largely ceremonial functions assigned to a single head of state but was provided little real power by the constitution.

The Soviet Union was established in 1922. However, the country's first constitution was only adopted in 1924. Before that time, the 1918 Constitution of the Russian Soviet Federative Socialist Republic functioned as the constitution of the USSR. According to the 1918 Constitution, the All-Russian Central Executive Committee (CEC), whose chairman was head of state, had the power to determine what matters of income and taxation would go to the state budget and what would go to the local soviets. The CEC could also limit taxes. In periods between convocations of the Congress of Soviets the CEC held supreme power. In between sessions of the Congress of Soviets the CEC was responsible for all the affairs of the Congress of Soviets. The CEC and the Congress of Soviets was replaced by the Presidium and the Supreme Soviet respectively by several amendments to the 1936 Constitution in 1938.

The Central Committee of the Communist Party of the Soviet Union was the highest organ of the Communist Party of the Soviet Union (CPSU) between Congresses. Elected by the Congress, the Central Committee emerged as the core nexus of executive and administrative authority in the party, with de facto supremacy over the government of the Soviet Union. It was composed of full members and candidate (non-voting) members. Real authority was often concentrated in smaller, more agile organs elected by the Committee, namely the Politburo, Secretariat, and Orgburo (dissolved in 1952), as well as in the post of General Secretary. Theoretically a collective leadership, the Committee increasingly became a rubber-stamp institution, particularly from the late 1920s onward under the dominance of Joseph Stalin.

The Central Committee originated in the Russian Social Democratic Labor Party (RSDLP), established in 1898, and continued in the Bolshevik party, established in 1912. After the Bolsheviks seized power in the October Revolution of 1917, the Committee assumed a key leadership role, functioning both as a strategic body and a conduit for implementing party directives in the expanding Soviet state. Stalin used his control over personnel appointments to dominate the Committee and ensure ideological conformity, and during his rule the Committee's composition often reflected factional struggles, purges, and leadership reshufflings. During the Great Purge of 1936 to 1938, a significant portion of its members were executed or imprisoned.

The Council of People's Commissars (CPC) (Russian: Совет народных комиссаров (СНК), romanized: Sovet narodnykh kommissarov (SNK)), commonly known as the Sovnarkom (Совнарком), were the highest executive authorities of the Russian Soviet Federative Socialist Republic (RSFSR), the Soviet Union (USSR), and the Soviet republics from 1917 to 1946.

The Sovnarkom of the RSFSR was founded in the Russian Republic soon after the October Revolution in 1917 and its role was formalized in the 1918 Constitution of the RSFSR to be responsible to the Congress of Soviets of the RSFSR for the "general administration of the affairs of the state". Unlike its predecessor the Russian Provisional Government which had representatives of various political parties, and except for the brief two-party cabinet with the Left Socialist-Revolutionaries from December 1917 to March 1918, the Sovnarkom was a government of a single party, the Bolsheviks. The Sovnarkom of the USSR and Congress of Soviets of the USSR founded in 1922 were modelled on the RSFSR system, and identical Sovnarkom bodies were founded in the Soviet republics and autonomous republics. The Sovnarkom evolved into the main executive of the government of the Soviet Union with its head, the Premier of the USSR, serving as head of government. The Sovnarkom issued decrees having the force of law when the Congress was not in session, and if these decrees were not approved at the Congress's next session, they were considered revoked.