Rubuta ci gaba don wannan sakin layi - Hugo ya sami ilimi a makarantar kwana da 'yan uwa mata ke jagoranta a Aalbeke kuma ya sha wahala lokacin da Jamus ta mamaye Belgium a lokacin Yaƙin Duniya na II. Kwarewar ta kasance mai tsarawa, kuma daga baya Claus zai daidaita shi a cikin littafinsa mai suna "The Sorrow of Belgium" (1983). Yawancin malaman Claus 'yan kishin Flemish ne wadanda suka nuna juyayi ga fascism, kuma Claus ya shiga reshen matasa na Jam'iyyar Flemish National Union. Mahaifinsa ma an tsare shi a takaice bayan 'Yanci
don haɗin kai. Mai nuna tausayi ga hagu na siyasa a wani lokaci mafi girma a rayuwarsa, Claus ya yaba da tsarin gurguzu bayan ziyarar Cuba a cikin shekarun 1960.