Vladimir Lenin in the context of "Mensheviks"

The Russian Revolution was a period of political and social change in Russia, starting in 1917. This period saw Russia abolish its monarchy and adopt a socialist form of government following two successive revolutions and a civil war. It can be seen as the precursor for other revolutions that occurred in the aftermath of World War I, such as the German Revolution of 1918–1919. The Russian Revolution was a key event of the 20th century.

The Russian Revolution was inaugurated with the February Revolution in 1917, in the midst of World War I. With the German Empire inflicting defeats on the front, and increasing logistical problems causing shortages of bread and grain, the Russian Army was losing morale, with large scale mutiny looming. Officials were convinced that if Tsar Nicholas II abdicated, the unrest would subside. Nicholas stepped down on 15 March [O.S. 2 March], ushering in a provisional government led by the Duma (parliament). During the unrest, Soviet councils were formed by locals in Petrograd (now Saint Petersburg) that initially did not oppose the new government; however, the Soviets insisted on their influence in the government and control over militias. By March, Russia had two rival governments. The Provisional Government held state power in military and international affairs, whereas the network of Soviets held domestic power. Critically, the Soviets held the allegiance of the working class, and urban middle class. There were mutinies, protests and strikes. Socialist and other leftist political organizations competed for influence within the Provisional Government and Soviets. Factions included the Mensheviks, Social Revolutionaries, Anarchists, and the Bolsheviks, a far-left party led by Vladimir Lenin.

The Bolsheviks, led by Vladimir Lenin, were a radical faction of the Marxist Russian Social Democratic Labour Party (RSDLP) which split with the Mensheviks at the Second Party Congress in 1903. The Bolshevik party, formally established in 1912, seized power in Russia in the October Revolution of 1917 and was later renamed the Russian Communist Party, All-Union Communist Party, and ultimately the Communist Party of the Soviet Union. Its ideology, based on Leninist and later Marxist–Leninist principles, became known as Bolshevism.

The origin of the RSDLP split was Lenin's support for a smaller party of professional revolutionaries, as opposed to the Menshevik desire for a broad party membership. The influence of the factions fluctuated in the years up to 1912, when the RSDLP formally split in two. The political philosophy of the Bolsheviks was based on the Leninist principles of vanguardism and democratic centralism. Lenin was also more willing to use illegal means such as robbery to fund the party's activities. By 1917, influenced by the experiences of World War I, he reached the conclusion that the chain of world capitalism could "break at its weakest link" in Russia before it assumed the level of the advanced countries, opposing theorists such as Georgi Plekhanov. Lenin had also come to view poorer peasants as potential allies of the relatively small Russian proletariat.

Joseph Vissarionovich Stalin (né Dzhugashvili; 18 December [O.S. 6 December] 1878 – 5 March 1953) was a Soviet politician, dictator and revolutionary who led the Soviet Union from 1924 until his death in 1953. His rule oversaw mass atrocities that caused an estimated 20 million deaths, and he is widely considered one of the most brutal despots of the modern era. He held office as General Secretary of the Communist Party from 1922 to 1952 and as premier from 1941 until his death. Despite initially governing the country as part of a collective leadership, he eventually consolidated power to become a dictator by the 1930s. Stalin codified the party's official interpretation of Marxism as Marxism–Leninism, and his version of it is referred to as Stalinism.

Born into a poor Georgian family in Gori, Russian Empire, Stalin attended the Tiflis Theological Seminary before joining the Marxist Russian Social Democratic Labour Party. He raised funds for Vladimir Lenin's Bolshevik faction through bank robberies and other crimes, and edited the party's newspaper, Pravda. He was repeatedly arrested and underwent several exiles to Siberia. After the Bolsheviks seized power in the October Revolution of 1917, Stalin served as a member of the Politburo, and from 1922 used his position as General Secretary to gain control over the party bureaucracy. After Lenin's death in 1924, Stalin won the leadership struggle over rivals including Leon Trotsky. Stalin's doctrine of socialism in one country became central to the party's ideology, and his five-year plans starting in 1928 led to forced agricultural collectivisation, rapid industrialisation, and a centralised command economy. His policies contributed to a famine in 1932–1933 which killed millions, including in the Holodomor in Ukraine. Between 1936 and 1938, Stalin executed hundreds of thousands of his real and perceived political opponents in the Great Purge. Under his regime, an estimated 18 million people passed through the Gulag system of forced labour camps, and more than six million people, including kulaks and entire ethnic groups, were deported to remote areas of the country.

The Union of Soviet Socialist Republics (USSR), commonly known as the Soviet Union, was a transcontinental country that spanned much of Eurasia from 1922 until it dissolved in 1991. During its existence, it was the largest country by area, extending across eleven time zones and sharing borders with twelve countries, and the third-most populous country. An overall successor to the Russian Empire, it was nominally organized as a federal union of national republics, the largest and most populous of which was the Russian SFSR. In practice, its government and economy were highly centralized. As a one-party state governed by the Communist Party of the Soviet Union (CPSU), it was the flagship communist state. Its capital and largest city was Moscow.

The Soviet Union's roots lay in the October Revolution of 1917. The new government, led by Vladimir Lenin, established the Russian SFSR, the world's first constitutionally communist state. The revolution was not accepted by all within the Russian Republic, resulting in the Russian Civil War. The Russian SFSR and its subordinate republics were merged into the Soviet Union in 1922. Following Lenin's death in 1924, Joseph Stalin came to power, inaugurating rapid industrialization and forced collectivization that led to significant economic growth but contributed to a famine between 1930 and 1933 that killed millions. The Soviet forced labour camp system of the Gulag was expanded. During the late 1930s, Stalin's government conducted the Great Purge to remove opponents, resulting in large scale deportations, arrests, and show trials accompanied by public fear. Having failed to build an anti-Nazi coalition in Europe, the Soviet Union signed a non-aggression pact with Nazi Germany in 1939. Despite this, in 1941 Germany invaded the Soviet Union in the largest land invasion in history, opening the Eastern Front of World War II. The Soviets played a decisive role in defeating the Axis powers while liberating much of Central and Eastern Europe. However they would suffer an estimated 27 million casualties, which accounted for most losses among the victorious Allies. In the aftermath of the war, the Soviet Union consolidated the territory occupied by the Red Army, forming satellite states, and undertook rapid economic development which cemented its status as a superpower.

A communist state, also known as a Marxist–Leninist state, is a form of government that combines the state leadership of a communist party, Marxist–Leninist political philosophy, and an official commitment to the construction of a communist society. Modern communism broadly grew out of the socialist movement in 19th-century Europe as a program to replace capitalism with a stateless, classless, and moneyless society, but its application as Marxism–Leninism began later in the Soviet Union under Joseph Stalin.

In the 20th century, several communist states were established, first in Russia with the Russian Revolution of 1917 and then in portions of Eastern Europe, Asia, and a few other regions after World War II. The institutions of these states were heavily influenced by the writings of Karl Marx, Friedrich Engels, Vladimir Lenin, Joseph Stalin and others. However, the political reforms of Soviet leader Mikhail Gorbachev known as Perestroika and socio-economic difficulties produced the revolutions of 1989, which brought down all the communist states of the Eastern Bloc bar the Soviet Union. The repercussions of the collapse of these states contributed to political transformations in the Soviet Union, Yugoslavia, and several other non-European communist states. Presently, there are five states which are officially communist in the world: China, Cuba, Laos, North Korea and Vietnam.

The supreme state organ of power (SSOP) is a type of legislature and the highest representative institution in communist states operating under the Marxist–Leninist principle of unified power. Unlike systems based on the fusion or separation of powers, the SSOP holds legislative, executive, judicial, and all other forms of state power. Formally regarded as the embodiment of popular sovereignty and the head of the unified state apparatus, its activities in practice are closely shaped by the ruling communist party.

The SSOP's theoretical origins trace back to Jean-Jacques Rousseau's idea of a “supreme power” of the people, Karl Marx’s call for unity of state power, and Vladimir Lenin’s vision of soviets as working organs which combined lawmaking and execution. The world's first SSOP was the All-Russian Congress of Soviets, established after the 1917 October Revolution, and it became the prototype for similar institutions in other communist states.

Polemic (/pəˈlɛmɪk/ pə-LEHM-ick, US also /-ˈlimɪk/ -⁠LEEM-ick) is contentious rhetoric intended to support a specific position by forthright claims and to undermine the opposing position. The practice of such argumentation is called polemics, which are seen in arguments on controversial topics. A person who writes polemics, or speaks polemically, is called a polemicist. The word derives from Ancient Greek πολεμικός (polemikos) 'warlike, hostile', from πόλεμος (polemos) 'war'.

Polemics often concern questions in religion or politics. A polemical style of writing was common in Ancient Greece, as in the writings of the historian Polybius. Polemic again became common in medieval and early modern times. Since then, famous polemicists have included satirist Jonathan Swift, Italian physicist and mathematician Galileo, French theologian Jean Calvin, French Enlightenment writer, historian, and philosopher Voltaire, Russian author Leo Tolstoy, socialist philosophers Karl Marx and Friedrich Engels, novelist George Orwell, playwright George Bernard Shaw, communist revolutionary Vladimir Lenin, linguist Noam Chomsky, social critics H. L. Mencken, Christopher Hitchens and Peter Hitchens, and existential philosophers Søren Kierkegaard and Friedrich Nietzsche.

The Russian Civil War (Russian: Гражданская война в России, romanized: Grazhdanskaya voyna v Rossii) was a multi-party civil war in the former Russian Empire sparked by the 1917 overthrowing of the Russian Provisional Government in the October Revolution, as many factions vied to determine Russia's political future. It resulted in the formation of the Russian Socialist Federative Soviet Republic and later the Soviet Union in most of its territory. Its finale marked the end of the Russian Revolution, which was one of the key events of the 20th century.

The Russian monarchy ended with the abdication of Tsar Nicholas II during the February Revolution, and Russia was in a state of political flux. A tense summer culminated in the October Revolution, where the Bolsheviks overthrew the provisional government of the new Russian Republic. Bolshevik seizure of power was not universally accepted, and the country descended into a conflict which became a full-scale civil war in May–June 1918. The two largest combatants were the Red Army, fighting for the establishment of a Bolshevik-led socialist state headed by Vladimir Lenin, and the forces known as the White movement (and its White Army), led mainly by the right-leaning officers of the Russian Empire, united around the figure of Alexander Kolchak. In addition, rival militant socialists, notably the Ukrainian anarchists of the Makhnovshchina and Left Socialist-Revolutionaries, were involved in conflict against the Bolsheviks. They, as well as non-ideological green armies, opposed the Bolsheviks, the Whites and the foreign interventionists. Thirteen foreign states intervened against the Red Army, notably the Allied intervention, whose primary goal was re-establishing the Eastern Front of World War I. Three foreign states of the Central Powers also intervened, rivaling the Allied intervention with the main goal of retaining the territory they had received in the Treaty of Brest-Litovsk with Soviet Russia.

The republics are one type of federal subject of the Russian Federation. Twenty-one republics are internationally recognized as part of Russia; another is under its de facto control. The original republics were created as nation states for ethnic minorities. The indigenous ethnicity that gives its name to the republic is called the titular nationality. However, due to centuries of Russian migration, a titular nationality may not be a majority of its republic's population. By 2017, the autonomous status of all republics was formally abolished, making the republics politically equivalent to the other federal subjects of Russia.

Formed in the early 20th century by Vladimir Lenin and the Bolsheviks after the collapse of the Russian Empire in 1917, republics were intended to be nominally independent regions of Soviet Russia with the right to self-determination. Lenin's conciliatory stance towards Russia's minorities made them allies in the Russian Civil War and with the creation of the Soviet Union in 1922 the regions became autonomous republics, albeit subordinate to a union republic. While officially autonomous, the autonomies of these administrative units varied throughout the history of the Soviet Union but largely remained under the control of the central government. The 1980s saw an increase in the demand of autonomy as the Soviet Union began large scale reforms of its centralized system. In 1990, most of the autonomous republics declared their sovereignty. The Soviet Union collapsed in 1991 and Russia became independent. The current republics were established with the signing of the Federation Treaty in 1992, which gave them substantial rights and autonomy.