The name was chosen in opposition to the "Black Brigade",[4][5] a collaborator group led by SS-Untersturmführer Reimond Tollenaere, who was responsible for the propaganda of pro-German Flemish National League.

The Witte Brigade was based in Antwerp[3] but had smaller branches in Gent, Lier, Aalst, Brussels, Waasland, Wallonia and in the coastal region.

[4] Important activities of the Witte Brigade were distributing anti-German propaganda, the creation of lists of collaborators and organizing patriotic demonstrations on key Belgian holidays, such as 21 July (National Day) and 11 November (Anniversary of the German surrender in the First World War).

[10] Despite their heavy losses, the Witte Brigade, along with the Armée secrète, the Front de l'Indépendance, the Mouvement National Royaliste and Groupe G, helped allied forces capture the port of Antwerp intact in 1944.

The Witte Brigade prevented the Germans, who had attached explosives to docks and cranes, from scuttling the facilities’ infrastructure, allowing the port to be opened once the Scheldt was cleared of sea mines.

The organization had been known popularly as the "White Brigade" so, after liberation, the group changed its name, adding the word "Fidelio", the pseudonym of Louette.