Paul Levi was born in Hechingen on 11th March 1883. Trained as a lawyer, he joined the Social Democratic Party (SDP) in 1906. At the time the SDP was deeply divided into three groups. The leader of the right-wing, Eduard Bernstein, had published a series of articles where he argued that the predictions made by Karl Marx about the development of capitalism had not come true. He pointed out that the real wages of workers had risen and the polarization of classes between an oppressed proletariat and capitalist, had not materialized. Nor had capital become concentrated in fewer hands.
The chairman of the party, August Bebel, remained a Marxist but believed that socialism could best be obtained through the parliamentary system. Paul Frölich has argued: "The SPD divided into three clear tendencies: the reformists, who tended increasingly to espouse the ruling-class imperialist policy; the so-called Marxist Centre, which claimed to maintain the traditional policy, but in reality moved closer and closer to Bernstein's position; and the revolutionary wing, generally called the Left Radicals (Linksradikale)." Levi became a member of the Left Radicals. Headed by Rosa Luxemburg it included Clara Zetkin, Karl Liebknecht, Franz Mehring, Karl Radek and Anton Pannekoek.
In 1906 Luxemburgpublished her thoughts on revolution in The Mass Strike, the Political Party and the Trade Unions. She argued that a general strike had the power to radicalize the workers and bring about a socialist revolution. "The mass strike is the first natural, impulsive form of every great revolutionary struggle of the proletariat and the more highly developed the antagonism is between capital and labour, the more effective and decisive must mass strikes become. The chief form of previous bourgeois revolutions, the fight at the barricades, the open conflict with the armed power of the state, is in the revolution today only the culminating point, only a moment on the process of the proletarian mass struggle."
These views were not well received by August Bebel and other party leaders. In a letter to Clara Zetkin she wrote: "The situation is simply this: August Bebel, and still more so the others, have completely spent themselves on behalf of parliamentarism and in parliamentary struggles. Whenever anything happens which transcends the limits of parliamentarism, they are completely hopeless - no, even worse than that, they try their best to force everything back into the parliamentary mould, and they will furiously attack as an enemy of the people anyone who wants to go beyond these limits."
Levi was persuaded by Luxemburg ideas and he became her lawyer. Levi was also a leading figure in the anti-militarist section of the SDP. In 1907 Karl Liebknecht published Militarism and Anti-Militarism. In the book he argued: "Militarism is not specific to capitalism. It is moreover normal and necessary in every class-divided social order, of which the capitalist system is the last. Capitalism, of course, like every other class-divided social order, develops its own special variety of militarism; for militarism is by its very essence a means to an end, or to several ends, which differ according to the kind of social order in question and which can be attained according to this difference in different ways. This comes out not only in military organization, but also in the other features of militarism which manifest themselves when it carries out its tasks. The capitalist stage of development is best met with an army based on universal military service, an army which, though it is based on the people, is not a people’s army but an army hostile to the people, or at least one which is being built up in that direction."
Liebknecht was the only member of the Reichstag who voted against Germany's participation in the First World War. He argued: "This war, which none of the peoples involved desired, was not started for the benefit of the German or of any other people. It is an Imperialist war, a war for capitalist domination of the world markets and for the political domination of the important countries in the interest of industrial and financial capitalism. Arising out of the armament race, it is a preventative war provoked by the German and Austrian war parties in the obscurity of semi-absolutism and of secret diplomacy."
Levi agreed with Karl Liebknecht but was conscripted into the German Army. However, by 1916 he had managed to escape to Switzerland where he joined Vladimir Lenin and Karl Radek in exile. He later returned to Germany where he joined forces with Liebknecht, Rosa Luxemburg, Leo Jogiches, Ernest Meyer, Franz Mehring and Clara Zetkin to establish an underground political organization called Spartakusbund (Spartacus League). The Spartacus League publicized its views in its illegal newspaper, Spartacus Letters. Liebknecht, like the Bolsheviks in Russia, began arguing that socialists should turn this nationalist conflict into a revolutionary war.
In 1918 Levi helped establish the German Communist Party (KPD). He opposed the Spartakist Rising in January, 1919, and after the executions of Rosa Luxemburg, Leo Jogiches and Karl Liebknecht he became the leader of the KPD. His moderate approach to socialism increased the size of the party. Levi headed the German delegation to the 2nd World Congress of the Communist International in Moscow in 1920.
Levi remained a supporter of the theories of Rosa Luxemburg and this brought him into conflict with Vladimir Lenin and Leon Trotsky. They were especially upset with the publication of Our Path: Against Putschism. In 1921 Levi resigned as chairman of the KPD over policy differences. Later that year, Lenin and Trotsky, demanded that he should be expelled from the party. The following year he arranged for Luxemburg's book The Russian Revolution to be published.
In 1922 Levi became active in the Independent Socialist Party. However, he eventually rejoined the Social Democratic Party. Because of his Jewish roots, he became the target of a hateful anti-Semitic campaign in the press.He responded by attacking prominent Nazis, such as Adolf Hitler, Ernst Roehm, Alfred Rosenberg and Wilhelm Frick in left-wing publications.
Paul Levi died on 9th February, 1930, after he fell from the window of his apartment in Berlin.