This book offers a detailed examination of Trotsky’s career and the contributions he made to the Soviet Union, both as a participant and later as a critic. Fourteen chapters cover the span of Trotsky’s life - from his early life and rise to prominence, to the major achievements of his political career and his decline and assassination in 1940. The final chapter considers different historical interpretations of Leon Trotsky and explains the debate surrounding key controversies in his career.