This painting in question of a German representing death (see his Pickelhaube on the piano) and a dead (most likely Entente) nurse. Or maybe it's a sketch but it looks like paint to me. What is the name of this piece? Perhaps the context is the Rape of Belgium?
This is one of many artistic depictions of similar themes. Miss Edith Cavell was a British nurse, working in occupied Belgium who in addition to to medical duties was actively involved in helping the escape of many British personnel. She was captured by the Germans, accused of espionage, and executed on 12 October 1915. This issue became a major propaganda victory for the British, and she was remembered in many paintings. Frequently, the executioner is shown as death, often in German uniform. The original title of this particular painting is "The Murder Of Miss Clavell inspires German "Kultur"". Several other similar illustrations are found on the web at: https://www.google.com/search?q=edith+Cavell+painting&client=firefox-b-ab&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwjrwqWw89raAhUBB3wKHegJCi8Q7AkINA&biw=1192&bih=664#imgrc=Y2vFkMjFfscR-M: Whether or not she was actually involved in espionage has been an argument ever since, with the Germans claiming yes, and the British claiming no. But, in 2015, Dame Stella Rimington, the former director-general of MI5, made a startling claim on the centenary of Cavell's death. In a BBC programme, she was to assert that Cavell's network was indeed smuggling intelligence back to the Allies. (https://www.telegraph.co.uk/news/bbc/11861398/Revealed-New-evidence-that-executed-wartime-nurse-Edith-Cavells-network-was-spying.html) But in any case, this is certainly an illustration of the Edith Cavell story.....
While I haven't found exact matches to your poster, it looks like it's in reference to the executiion of Edith Cavell in 1915.
Cavell was a British nurse who was the head of the first Belgian nursing school in Brussels. Upon occupation of Brussels by the German army in World War I, her school was converted to a Red Cross hospital, and served the wounded from both sides of the conflict.
However, Cavell also helped British, French and Belgians escape from occupied Belgium and rejoin their respective forces. For this she was arrested, tried and executed in October of 1915. The execution was technically legal under international law, but was a massive public relations blunder on Germany's part, and was milked for maximum propaganda value by the British.
Some similar Cavell posters are here much like the OP picture they have Cavell laid out the same way. The uniform in your poster also looks like a Red Cross nurse's uniform similar to Cavell's in the other posters, and her being draped with a Union Jack indicates that we should assume it's supposed to be her.
Some info on Cavell from the Imperial War Museum here.
