Lev Grigorievich Deutsch was born September 25, 1855, in Tulchin, in the Podolia Governorate of the Russian Empire (today Tulchyn, Ukraine), the son of a Jewish merchant father and a peasant mother.

At the age of 19, he joined a Narodnik group in Kiev, and took part in the 'to the people' movement, in which young radicals dressed as peasants, and went to villages to spread socialist ideas.

Deutsch escaped to Europe, but returned to St Petersburg, and – despite his past record – was a founding member of Chornyi peredel (Black Repartition), rather than the more violent and conspiratorial People's Will, who carried out the assassination of the Tsar.

In 1880 Deutsch and other leaders of the Black Repartition group, including George Plekhanov, Vera Zasulich and Pavel Axelrod emigrated to Geneva.

It was extremely rare for Russian revolutionaries to be extradited by any European government, but Deutsch was treated as a common criminal because the attempt to kill Gorinovich, and sent back to St Petersburg in a cattle truck.

"[3] In 1900, Deutsch made a dramatic escape from Siberia, through Japan, the US, Liverpool, London, and Paris, to rejoin the Emancipation of Labour League in Switzerland in November 1901.

His three former comrades there had since joined Vladimir Lenin, Julius Martov, and Alexander Potresov on the six-member editorial board of the newspaper Iskra, which was riven by rivalry between the generations.

[4] Deutsch was present as an observer at the second congress of the Russian Social Democratic Labour Party in 1903 when it split into its Bolshevik and Menshevik factions.

He successfully lobbied the editors of Iskra to allow Trotsky to stay in Europe, rather than be assigned to illegal work in Russia, with a high risk that he would be arrested.