1 Trotsky was born Lev Davidovich Brostein, on 7th November 1879 in Yanovka,
2 Involved in underground activities as teenager, and was arrested and
sent to Siberia where he joined the Social Democratic party. Eventually
escaped Siberia and lived abroad for 15 years.
2.1 In 1903 Social Democrats split and Trotsky joined the Menshevik faction. He then developed his theory of 'permanent revolution'.
He often tried to reconcile the Mensheviks and Bolsheviks leading to clashes with leaders of both parties, including Lenin.
3 After 1917 revolution Trotsky returned to Russia
and despite previous disagreements with Lenin
joined the Bolshevik party.
4 Saw provisional government as inneffectual.
4.1 Kerensky saw him as a major threat and had him arrested. Joined
Bolshevik party while in jail and released soon after.
5 Elected Chairman of Petrograd Soviet after release from prison.