I had no idea about the Shelling of Mainila; further reading suggests it closely followed the Molotov-Ribbentrop Pact, where Nazi Germany and the Soviet Union agreed to be at peace with each other, while also planning the annexation of Poland, Lithuania, Latvia, Estonia and Finland. That was on August 23, 1939; Nazi Germany then invaded Poland on September 1, 1939. That gives me shivers.
The Shelling of Mainila followed two months later.
Excellent job on the graphics! I'm really enjoying this build. Please tell me what it says on the box of orange tape; I can only make out part of it.