Fedrelandslaget was disestablished in 1940, when Nazi Germany invaded Norway on 9 April 1940 as a part of World War II. The Nazi Vidkun Quisling performed a coup d'état, but Mogens tried to have Quisling removed, as he was still hoping that Fedrelandslaget and not Quisling's party Nasjonal Samling would be the main cooperator with the German occupants. On 26 April 1940, the Bremen-based broadcaster of Norwegian-language propagandistic news, Edvard Sylou-Creutz, lamented the absence of Mogens as a commentator, stating that if Mogens had continued, the Norwegian people might have been more friendly towards Germany.