Joris Van Severen was a Belgian politician and ideologue of the Flemish Movement as well as a Pan-Netherlander. A leading figure of pre-World War II Flemish nationalism, he co-founded the extreme-right group Verdinaso.

The Flemish Movement is an umbrella term which encompasses various political groups in the Belgian region of Flanders and, less commonly, in French Flanders. Ideologically, it encompasses groups which have sought to promote Flemish culture and the Dutch language as well as those seeking greater political autonomy for Flanders within Belgium. It also encompassed nationalists who seek the secession of Flanders from Belgium, either through outright independence or unification with the Netherlands.