Léon Degrelle was born June 15th 1906, in Bouillon in the province of Luxemburg near the Belgian-French border. Between 1920 and 1924, he attended secondary school at the Jesuit college Notre Dame de la Paix (Our Sacred Lady of Peace) in Namur and went on to study law at the University of Louvain. He became editor of the student's magazine 'l'Avant Garde' and deemed this so important that he neglected his studies. He became the leader of the 'Association des Etudiants Catholiques à l'Université de Louvain' (Association of Catholic Students at Louvain University) and later on became involved in the 'Association de la Jeunesse Catholique Belge' (Association of Belgian Catholic Youth). In March 1929 he became the editor of the 'Cahiers de la Jeunesse Catholique', (Organ of Catholic Youth) the official paper of the movement.
At the end of October 1930, his mentor asked him to become editor-in-chief of the publishing firm Editions Rex, which published flyers by the name of Christ Rex for the Action Catholique (Catholic Movement). In that capacity he drew the attention of the Catholic Party which was looking for someone to handle their propaganda. Through his publishing firm, Degrelle got heavily involved in the 1932 elections, much to the disgust of the apolitical A.J.C.B. The papers he published, including Vlan, Soiree and Rex caused a lot of consternation among Catholics for their violent polemics on politics and political programs. In 1933, the A.J.C.B. set Degrelle an ultimatum but a final break with the Catholic Party did not occur until 1936.
Rex as a political movement was established on November 2nd, 1935, and initially enjoyed quite a following, because of Degrelle's eloquence and his attacks on socialism and capitalism. The elections on May 24th, 1936, resulting in 10 seats in parliament for the party were successful but afterwards, support for the party waned quickly. The party did not have a clear political program, hence had little to offer to its electorate and as a result, the elections of November 11th, 1937, ended in disaster and those of April 2nd, 1939, even meant the end of Rex as a political movement, also ending Degrelle's career as a politician.
After the German occupation in 1940, Rex declared its solidarity with the Nazis and consequently, Degrelle was arrested along with some others for his pro-German activities. He was deported to France where he was kept imprisoned at Abbéville and subsequently in Vernet, close to the Spanish border. He was liberated on July 22nd, 1940 and returned to Belgium. Once there he tried to rekindle his political activities but without any real success.