Karl Liebknecht was a German socialist and revolutionary born on August 13, 1871. He was a prominent figure in the German Social Democratic Party and later co-founded the Spartacus League, which aimed to promote socialist ideas. Liebknecht was known for his opposition to World War I, famously declaring that the war was a conflict between imperialist powers. In 1919, Liebknecht played a key role in the German Revolution, which sought to establish a socialist government in Germany. He was arrested and later executed by the government during the uprising. His legacy continues to influence leftist movements in Germany and beyond.