Marx Brothers and the Marx Brothers. Most of the comedians provided their own voices for their animated counterparts, except for Fields and Chico Marx (both had died), and Zeppo Marx (who had left show business in 1933). Voice actor Paul Frees filled in for all three (no voice was needed for Harpo). The Marx Brothers' segment was a reworking of a scene from their Broadway play "I'll Say She Is", a parody of Napoleon that Groucho considered among the brothers' funniest routines. The sketch featured animated representations, if not the voices, of all four brothers. Romeo Muller is credited as having written
Biographies of Karl Marx (1925), Japanese (1930), Spanish (1932), and English (1935). Marx: Man and Fighter is a biography by Boris Nicolaievsky, first published in German in 1933. It was translated into English by Otto Mänchen-Helfen and published in 1936. Some subsequent English editions restore the notes, appendices, and bibliography omitted from the first English edition. Karl Marx: His Life and Environment is a 1939 biography of Karl Marx by Isaiah Berlin, in which Berlin argues that Marx's system of thought depends upon indefensible metaphysical presuppositions. Karl Marx: His Life and Thought is a 1973 biography of Karl Marx by political scientist David McLellan.