Far-right political party in Belgium from 1935-45
Source (Wikipedia): Rexist Party

The Rex Popular Front, Rexist Party, or simply Rex, was a far-right Catholic authoritarian and corporatist political party active in Belgium from 1935 until 1945. The party was founded by a journalist, Léon Degrelle, It advocated Belgian unitarism and royalism. Initially, the party ran in both Flanders and Wallonia, but it never achieved much success outside Wallonia and Brussels. Its name was derived from the Roman Catholic journal and publishing company Christus Rex.