The League was founded on 4 June 1898 by the republican Ludovic Trarieux to defend captain Alfred Dreyfus, a Jew wrongly convicted for treason - this would be known as the Dreyfus Affair.
Dissolved by the anticommunist regime of Vichy during World War II, it was clandestinely reconstituted in 1943 by a central committee including Pierre Cot, René Cassin and Félix Gouin.