The French Revolution of 1789, sparked off an extraordinary explosion of political, economic and social agitation, the effects of which are still felt today in all parts of the world. German philosophers, French politicians, Russian aristocrats, poets and working-men of varying nationalities and origins were caught up in this ferment; but its two towering figures were Marx and Engels, the archangels of the international Socialist movement. The great German poet, Heine, called them "Doctors of the Revolution", and this term is used to include other unique and passionate fighters for social justice and equality who are described here: firebrands like Bakunin, Herzen, Hess, Lassalle and many more. This book explores the complex ties that bound these characters to one another throughout their lives in relationships covering the whole gamut from admiration to animosity, manipulation and violent clashes. This is an account of these apostles of the rival creeds of Communism, Socialism, Anarchism, Russian Populism, Bolshevism as well as Zionism, whose conflicts and triumphs have dominated our own ideology-ridden century.