 When his father died in 1914 in World War I, the family (mother, grandparents and Otakar with 3 siblings) moved to town Německý Brod.In 1928 he started studying law in Brno and entered Young Communist League of Czechoslovakia ("Komsomol").In 1930 he was arrested and imprisoned as a leader of a group of students that painted anti-war slogans (his anti-militarism can be traced back to loss of his father and to the influence of his mother and grandfather Kadleček) on a church in Německý Brod.