Karl Johann Kautsky (October 16, 1854 – October 17, 1938) was a Czech-Austrian philosopher, journalist, and Marxist theoretician. Kautsky was recognized as among the most authoritative promulgators of Orthodox Marxism after the death of Friedrich Engels in 1895 until the outbreak of World War I in 1914 and was called by some the "Pope of Marxism." Following the war, Kautsky was an outspoken critic of the Bolshevik Revolution and its excesses, engaging in polemics with V.I. Lenin and Leon Trotsky on the nature of the Soviet state.