Theodore Rothstein

Theodore Rothstein (Russian: Фёдор Аронович Ротштейн, Fyodor Aronovich Rotshteyn; 26 February 1871 – 30 August 1953) was a Soviet politician, journalist, writer and communist.

[2] Rothstein occupied the left-wing of the party as a prominent theorist and forward thinker, and in 1900 he was elected to its executive.

He also joined the Russian Social Democratic Labour Party as a British member in 1901, siding with the Bolshevik faction against the Mensheviks and becoming a close comrade of Lenin, who often stayed at Rothstein's house on Clapton Square in the Hackney area of London.

Within the SDF's successor, the British Socialist Party (BSP), he was a leader of the opposition to Hyndman's support for the war.

On 6 January 1921 Rothstein was accredited as the first[5] Soviet Ambassador to Tehran and departed for the posting on 6 February after having had a discussion with Lenin.