What would be the effects of a Russian Victory in their invasion of East Prussia, Germany, in 1914? This was certainly possible as the invading Russian Army was more than 3 times larger than the German defending force. 800,000 Russians vs 250,000 Germans. Perhaps with more Co-operation between the invading Russian armies, more Aggressive Russian Generals, and the Russians using codes in their communications to conceal information from the Germans (something the Russians did not do in real life in this battle), with these things the Russians likely would have won.
But what happens then? Do the Germans fall back to the Vistula river (Something they actually considered doing). Do they move more armies away from France and to the east (and risk getting pushed out of France and the French recovering their industrial centers in the north east, which accounted for 40% of French steel and coal). Do the Germans consider suing for peace, since the Russians are now within striking distance of Berlin?
The Germans losing eastern Prussia would be a crushing blow to morale, since Eastern Prussia is (part of) the historical heart of the German Reich. Meanwhile the Russians still have their armies, as they are victorious, that means they weren't (partially) encircled and destroyed. These still whole armies could, with some preparation, help toward a potential push toward the Oder river.
But what happens then? Do the Germans fall back to the Vistula river (Something they actually considered doing). Do they move more armies away from France and to the east (and risk getting pushed out of France and the French recovering their industrial centers in the north east, which accounted for 40% of French steel and coal). Do the Germans consider suing for peace, since the Russians are now within striking distance of Berlin?
The Germans losing eastern Prussia would be a crushing blow to morale, since Eastern Prussia is (part of) the historical heart of the German Reich. Meanwhile the Russians still have their armies, as they are victorious, that means they weren't (partially) encircled and destroyed. These still whole armies could, with some preparation, help toward a potential push toward the Oder river.