At the end of World War II, Art Deco in Brussels faded to make way for the modernist and international architectural styles that would mark the postwar period.

[1] The architects of the Vienna Secession (formed in 1897), especially Josef Hoffmann, had a notable influence on Art Deco and early modernism in Brussels.

His Stoclet Palace (1905–1911) on the Avenue de Tervueren/Tervurenlaan in Woluwe-Saint-Pierre, was a prototype of the Art Deco style, featuring geometric volumes, symmetry, straight lines, concrete covered with marble plaques, finely-sculpted ornament, and lavish interiors, including mosaic friezes by Gustav Klimt.

[3] The post-World War I austerity meant that Art Nouveau was no longer affordable or fashionable for Brussels' upper middle class.

On his return to Brussels in January 1919, following his exile to the United States, Victor Horta, who had gradually been simplifying his style over the previous decade, abandoned organic forms, and instead based his designs on the geometrical.