Alexei Nikolayevich Kosygin (21 February [O.S. 8 February] 1904–18 December 1980) was a Soviet statesman who served as the Chairman of the Council of Ministers from 1964 to 1980. Following Khrushchev's removal from power, he briefly led the Soviet Union as part of a triumvirate in the mid-to-late 1960s.

Kosygin was born in the city of Saint Petersburg in 1904 to a Russian working-class family. During the Russian Civil War, he was conscripted into the labour army. After the Red Army's demobilization in 1921, he worked in Siberia as an industrial manager. In the early 1930s, Kosygin returned to Leningrad and worked his way up the Soviet hierarchy. During the Great Patriotic War (World War II), Kosygin was tasked by the State Defence Committee with moving Soviet industry out of territories soon to be overrun by the German Army. He served as Minister of Finance for a year before becoming Minister of Light Industry (later, Minister of Light Industry and Food). However, in 1952, Stalin removed Kosygin from the Politburo, thereby weakening Kosygin's position within the Soviet hierarchy.

Following Stalin's death in 1953, Kosygin was appointed to the position of chairman of the State Planning Committee (Gosplan) on 20 March 1959. Later, in 1960, he was promoted First Deputy chairman of the Council of Ministers. When Nikita Khrushchev was removed from power on 14 October 1964, Kosygin and Leonid Brezhnev succeeded him as Chairman of the Council of Ministers and First Secretary of the Communist Party respectively. He then formed a triumvirate alongside Brezhnev and CC Secretary Nikolai Podgorny that led the Soviet Union in Khrushchev's place.

Upon Khrushchev's ouster, Kosygin initially emerged as the de facto leader of the Soviet regime. In addition to overseeing the country's economy, he assumed a preeminent role in directing its foreign policy. However, in 1968, the Prague Spring sparked a massive backlash against his reforms, thereby enabling Leonid Brezhnev to eclipse him as the dominant force within the Politburo. Despite having his standing significantly weakened within the Kremlin, Kosygin was allowed by Brezhnev to remain in office until his retirement in October 1980 due to bad health. He died two months later on 18 December 1980.

Kosygin was born into a Russian working-class family consisting of his father and mother (Nikolai Ilyich and Matrona Alexandrovna) and his siblings. The family lived in Saint Petersburg. Kosygin was baptized (7 March 1904) one month after his birth. He lost his mother in infancy and was brought up by his father.

He and his father sympathized with the Revolution and Alexei was conscripted into a labour army on the Bolshevik side at the age of 14 during the Russian Civil War of 1917–1922. After demobilization from the Red Army in 1921, Kosygin attended the Leningrad Co-operative Technical School and found work in the system of consumer co-operatives in Novosibirsk, Siberia. When asked why he worked in the co-operative sector of the economy, Kosygin replied, quoting a slogan of Vladimir Lenin: "Co-operation – the path to socialism!" Kosygin stayed there for six years until Robert Eikhe personally advised him to quit, shortly before the repressions hit the Soviet consumer co-operation movement.

He applied for a membership in the Communist Party of the Soviet Union in 1927 and returned to Leningrad in 1930 to study at the Leningrad Textile Institute [ru]; he graduated in 1935. After finishing his studies, Kosygin worked as a foreman and later a manager in a textile mill director. He rose rapidly during the Great Purge, overseen in Leningrad by the provincial communist party boss, Andrei Zhdanov. He was appointed director of the October Textile Factory in 1937, head of the Industry and Transport department of the Leningrad provincial communist party in July 1938, and in October 1938, Chairman of the Executive Committee of the Leningrad City Soviets of Working People's Deputies, i.e. 'mayor' of Leningrad City. In 1939, he was appointed People's Commissar for Textile and Industry and earned a seat on the Central Committee (CC). In 1940 Kosygin became a Deputy Chairman of the Council of People's Commissars.

Kosygin was appointed by the State Defence Committee to manage critically important missions during the Great Patriotic War (World War II).