Marxist theorist, a prominent member of the first Russian Social-Democratic Workers' Party, and one of the leaders of the reformist wing of Russian social democracy, known after 1903 as the Mensheviks (Menshevik).

Akselrod participated in the Narodnik (populist) movement during the 1870s and formed the revolutionary splinter group Black Repartition with Georgy Plekhanov (Plekhanov, Georgy Valentinovich) in 1879. Later traveling to western Europe, he became a Marxist and a founder of the Liberation of Labour (1883), the first organization committed to spreading Marxism in Russia. He also joined the editorial board of the Marxist newspaper Iskra (1900; “The Spark”). He adopted Menshevism at the Second Congress of Russian Social Democrats (1903), and for the next 15 years he was the leading ideologist of the Mensheviks (Menshevik). Akselrod called for Russian Marxists to abandon violent revolutionary activities and instead to concentrate their efforts on labour organizing and parliamentary work in the social democratic tradition of western Europe. Akselrod opposed Bolshevik leader Vladimir Lenin (Lenin, Vladimir Ilich)'s strategy of organizing a highly centralized Marxist political party led by professional revolutionaries, and he predicted that, if such a party were to gain power in Russia, it would simply replace the despotism of the autocratic tsar with its own form of despotism.

During World War I Akselrod favoured the defense of Russia, and he opposed the in October 1917. Afterward he lived in western Europe, where he was one of the leading Marxist critics of Leninist rule. His memoirs Perezhitoye i peredumanoye (“Experiences and Reflections”) were published in 1923.