Wilhelm Liebknecht (March 29th 1826 Gießen - August 7th 1900 Berlin) was a German Socialiste, cofounder of the social democrat Parti German ( Sozialdemokratische Partei Deutschlands ).

Between 1842 and 1846, Liebknecht philology, philosophy and Protestant theology at the universities of Gießen, Berlin and Marbourg. At the same time, he learned the trades from carpenter and arms manufacturer, in order to prepare with a possible emigration towards the United States. He approached the Saint-simonisme. In 1846, he was the leader of a student tumult with Gießen. Because of its political activities, it was obliged to emigrate towards Switzerland into 1847 before finishing its studies. In Zurich, he taught in a school influenced by the pedagog Friedrich Fröbel. He also started to work as correspondent for newspapers.

In February 1848, it remained in Paris at the time of the Révolution of 1848. Then, it took part in the German revolutions of 1848/49 in South-west as lieutenant in the working body-francs of Gustav Struve. It took refuge with Geneva where it met Friedrich Engels. Because of its political activities, the Swiss government expelled Liebknecht into 1850 towards London. Karl Marx showed Carl Vogt, another emigrant originaíre of Gießen, to have denounced Liebknecht.

In England, it joined the Bund der Kommunisten (Ligue of the Communists) of Marx and Engels. He worked as private teacher and journalist. In 1862, it could turn over to Germany after an amnesty for the revolutionists of 1848/49.

In 1867, with August Bebel, it founded the Sächsische Volkspartei ( Saxon Popular party ), then the SDAP ( Sozialdemokratische Arbeiterpartei , social democrat Parti the German workers , in 1869, which became the SPD in 1890.

On the initiative in particular of Friedrich Engels and Liebknecht in 1889 the constituted Second International.

Liebknecht Maria twice. In 1854, he married in London Ernestine Landolt and in 1868 in Darmstadt Natalie Reh. Natalie is, like Wilhelm, downward of the professor of theology and mathematics with the Université of Gießen Johann Georg Liebknecht (1679-1749). First marriage, it had two girls, Alice and Gertrud, and of the second marriage the lawyers and politicians social-democrats Theodor (1870-1948) and Karl Liebknecht.