171 years ago today, on October 16, 1854 (August 25, 1854 lunar calendar), the German socialist activist Kautsky was born. Karl Kautsky was born in Prague on October 16, 1854 and later moved to Vienna. In 1874, he entered the University of Vienna to study philosophy and was deeply influenced by the ideas of Malthus, Spencer, Müller and others. He opposed national oppression and became a radical democrat and nationalist. He joined the Austrian Social Democratic Party in 1875 and joined the German Socialist Workers Party two years later. In 1880, he went to Zurich as an assistant to the reformist Hirschberg. The following year, he met Marx and Engels in London and turned to Marxism. After Engels died, he wrote a criticism of Bernstein revisionism. From 1910 to become a representative of the Second International; shunned violent revolution. Supported the war after the outbreak of the First World War. In 1914, he wrote "Imperialism" and put forward the "theory of ultra-imperialism". In April 1917, he formed the German Independent Social Democratic Party. Opposed the Russian October Revolution and the Soviet regime. Joined the government in 1918. In 1924, he wrote "The Materialist View of History" and systematically expounded his ideological views. After Hitler came to power, he went into exile abroad. He died in Amsterdam on October 17, 1938.