I painted the artwork "Joachim at the forest near Kursk in 1943".
Actually, Leutnant Joachim Linde (he is my original character of the story) has trained for artillery in 1938, but he had to work at "Artilleriebeobachter or Vorgeschobener Beobachter(the forward observer unit)" on command in 1939.
In July 1940, he went to Northern France or Belgium and has guarded the national border "Siegfried Line".(Heeresgruppe A) After this, he (who became Oberleutnant) volunteered for "Sturmgeschütz Abteilung" (it's "Sturmartillerie." this means that the assault gun battalion) in Heerestruppe and has transferred to there of "IV Armeekorps" in June 1941.
So, this is a scene before the battle with their enemy in 1943. Hauptmann Linde is waiting his enemy while reading a letter from his girlfriend. though he doesn't want to battle with nobody...he is feeling to sad about war, but he becomes happy by her words.
*This is Deviantart page. Thanks for the adding in "German history" page!