With the violation of Belgian neutrality by the Nazis on 10 May 1940, the Rexist Party split over the matter of resistance. Many Rexists went underground and began resisting the German occupation. Others, most notably Degrelle, sided with the Germans. Degrelle was arrested for collaborating with the Germans and was evacuated to France, where he was eventually released by the Germans. Upon his release, he returned to Belgium and joined the Walloon Legion. Degrelle would eventually rise to the rank of SS-Obersturmbannführer (Lieutenant Colonel), and become one of only two foreigners to be awarded the Knight’s Cross with Oak Leaves.
At the end of the war, Degrelle fled to Denmark and Norway, where he then commandeered a Heinkel He 111 aircraft and fled to Spain. Franco’s government refused to turn over Degrelle for extradition, even going so far as to allow him to escape from the hospital where he was staying while handing over a look-alike. In 1954, Spain granted him Spanish citizenship under the name José León Ramírez Reina. Belgium convicted him of treason in absentia and condemned him to death by firing squad.
Degrelle would remain in Spain until his death in 1994.