Gregory Zinoviev was born in Yelizavetgrad, Ukraine, Russia on 23rd September, 1883. The son of a Jewish diary farmers, Zinoviev received no formal schooling and was educated at home. At the age of fourteen he found work as a clerk.

Zinoviev joined the Social Democratic Party in 1901. He became involved in trade union activities and as a result of police persecution he left Russia and went to live in Berlin before moving on to Paris. In 1903 Zinoviev met Vladimir Lenin and George Plekhanov in Switzerland.

At the Second Congress of the Social Democratic Party in London in 1903, there was a dispute between Vladimir Lenin and Jules Martov, two of the party's main leaders. Lenin argued for a small party of professional revolutionaries with alarge fringe of non-party sympathisers and supporters. Martov disagreed believing it was better to have a large party of activists. Martov won the vote 28-23 but Lenin was unwilling to accept the result and formed a faction known as the Bolsheviks. Those who remained loyal to Martov became known as Mensheviks.

Zinoviev joined the Bolsheviks. So also did Lev Kamenev, Anatoli Lunacharsky, Joseph Stalin, Mikhail Lashevich, Nadezhda Krupskaya, Alexei Rykov, Yakov Sverdlov, Mikhail Frunze, Maxim Litvinov, Vladimir Antonov, Felix Dzerzhinsky, Gregory Ordzhonikidze, and Alexander Bogdanov. Whereas George Plekhanov, Pavel Axelrod, Leon Trotsky, Lev Deich, Vladimir Antonov-Ovseenko, Irakli Tsereteli, Moisei Uritsky, Noi Zhordania and Fedor Dan supported Jules Martov.

In the autumn of 1903 Zinoviev returned to Russia where he became involved in the publication of Iskra. The following year he moved to Switzerland where he studied chemistry at Berne University. He also continued to contribute to Bolshevik journals such as Vperyod.

With the outbreak of the 1905 Revolution Zinoviev returned to Russia and helped organize the general strike in St. Petersburg. Taken seriously ill with heart trouble, Zinoviev was forced to abandon the struggle and receive treatment abroad.

Zinoviev returned to Russia in March, 1906, and over the next three years agitated amongst metalworkers in St. Petersburg. As one of the key leaders of the Bolsheviks, Zinoviev was involved in the struggle with the Mensheviks for control over the workers and the armed forces in the city.

In 1907 Zinoviev attended the London Party Congress and was elected to the six man Bolshevik Central Committee. The following year Zinoviev was arrested by the Okhrana but was later released without charge.

Afraid of being re-arrested, Zinoviev moved to Geneva where he worked with Vladimir Lenin and Lev Kamenev in the publication of Proletary. Although living in exile, he helped to organize the publication of Zvezda and Pravda in St. Petersburg.

In 1912 Zinoviev, Lev Kamenev and Vladimir Lenin moved to Krakow in Galicia to be closer to Russia. On the outbreak of the First World War they were forced to move to the neutral Switzerland.

After the overthrow of Nicholas II in 1917, Zinoviev, Vladimir Lenin and Lev Kamenev returned to Russia and joined with Leon Trotsky and others in plotting against the government being led by Alexander Kerensky. Soon after arriving in St. Petersburg, Lenin and Zinoviev published their views on how to achieve a Marxist revolution. Zinoviev also became the new editor of Pravda.

The Bolshevik Party feared that Zinoviev and Vladimir Lenin would be arrested and so on the 9th July, 1917, they went into hiding. Zinoviev returned in August and worked for Proletary and Rabachii Put.

At a meeting of the Central Committee on 9th October, Zinoviev and Lev Kamenev were the only members opposed to Lenin's call for revolution. He later changed his mind and took part in the October Revolution that brought the Bolsheviks to power.

In February, 1917, Zinoviev was elected Chairman of the Council of Commissars of the Petrograd Workers' Commune. The following month he became Chairman of the Council of Commissars of the Union of Communes of the Northern Region. At the First World Congress of the Comintern in March, 1919, he was elected chairman of the Executive Committee.

Zinoviev reached the peak of his power in 1923 when with Joseph Stalin and Lev Kamenev became one of the Triumvirate that planned to take over from Vladimir Lenin when he died.

After the death of Lenin 1924, Zinoviev joined forces with Lev Kamenev and Joseph Stalin to keep Leon Trotsky from power. In 1925 Stalin was able to arrange for Trotsky to be dismissed as commissar of war and the following year the Politburo.

With the decline of Trotsky, Joseph Stalin felt strong enough to stop sharing power with Zinoviev and Lev Kamenev. Stalin now began to attack Trotsky's belief in the need for world revolution. He argued that the party's main priority should be to defend the communist system that had been developed in the Soviet Union. This put Zinoviev and Kamenev in an awkward position. They had for a long time been strong supporters of Trotsky's theory that if revolution did not spread to other countries, the communist system in the Soviet Union was likely to be overthrown by hostile, capitalist nations. However, they were reluctant to speak out in favour of a man whom they had been in conflict with for so long.

When Joseph Stalin was finally convinced that Zinoviev and Lev Kamenev were unwilling to join forces with Leon Trotsky against him, he began to support openly the economic policies of right-wing members of the Politburo like Nikolay Bukharin, Mikhail Tomsky and Alexei Rykov. They now realized what Stalin was up to but it took them to summer of 1926 before they could swallow their pride and join with Trotsky against Stalin.

When Zinoviev and Lev Kamenev eventually began attacking his policies, Joseph Stalin argued they were creating disunity in the party and managed to have them expelled from the Central Committee. The belief that the party would split into two opposing factions was a strong fear amongst active communists in the Soviet Union. They were convinced that if this happened, western countries would take advantage of the situation and invade the Soviet Union.

Under pressure from the Central Committee, Zinoviev and Lev Kamenev agreed to sign statements promising not to create conflict in the movement by making speeches attacking official policies. Leon Trotsky refused to sign and was banished to the remote area of Kazhakstan.

In 1935 Zinoviev was arrested and charged with being involved in the assassination of Sergy Kirov. Found guilty he was sentenced to 10 years' imprisonment. The following year he was charged with forming a terrorist organization to kill Joseph Stalin and other leaders of the government. Gregory Zinoviev was found guilty and executed in Moscow on 25th August, 1936.