[1] The letter's author, the philologist Adiel Debeuckelaere [nl], set out a number of grievances relating to the treatment of the Flemish within the Belgian Army fighting on the Yser Front during World War I, especially concerning the perceived inequality of French and Dutch languages.
[2] The letter was the most famous action of the Frontbeweging and is considered an important moment in the history of the Flemish Movement.
The letter expressed loyalty to Albert I and demanded autonomy, rather than independence, for Flanders within a Belgian framework.
It nonetheless provoked an angry reaction from the High Command which viewed the letter as subversive.
[3] Within German-occupied Belgium, a large faction of the Flemish Movement were collaborating with the German authorities as part of the Flamenpolitik and the letter defended their actions.