What if WW1 were held off until 1915? Let's say that set up is similar with a Serb nationalist assassinating Franz Ferdinand and A-H going for war and backed by Germany? France and Russia would come in the same way as IOTL and the Schlieffen/Moltke Plan is in effect. There are some key differences though: The Ottomans would have their battleships from Britain: https://en.wikipedia.org/wiki/HMS_Erin https://en.wikipedia.org/wiki/HMS_Agincourt_(1913) These would give them better battleships than the Russians in the Black Sea, but no motivation to fight in 1915, especially if the German cruisers don't end up in Ottoman ports, which they won't in this scenario. The British would have the problem of the Irish Home Rule Crisis to deal with: https://en.wikipedia.org/wiki/Home_Rule_Crisis#Unionist_opposition They would probably be bogged down in an early version of the Irish Civil War: https://en.wikipedia.org/wiki/Irish_Civil_War So Britain cannot join the war in 1915 or at least take active part. Russia would be able to mobilize slightly faster, the French army would be slightly bigger due to the Loi de Cadre extending conscript service to 3 years, while the A-Hs would have modernized their artillery much more and have modern howitzers in service (theirs were not using hydraulic recoil equipped guns; those they did have were bronze barrel guns from the 1880s). The German army would be roughly similar to 1914, but would actually have its new siege guns ready for Liege, unlike OTL (they had to be rushed from the factories to the frontline): https://en.wikipedia.org/wiki/Big_Bertha_(howitzer) What does this mean? Well, no BEF at Mons, Le Cateau, Etreux, or Nery in August-September, nor a BEF to march into the gap between German army at the Marne. There is also probably not likely a British force sent to Antwerp, though there might be a blockade of Germany by Britain. The A-Hs might do better in Galicia in 1914 with better artillery, but its unlikely. Germany would certainly do better in 1914 in France, especially without much if any British involvement if there is an ATL Race to the Sea. The Russian front is probably going to play out similar. IMHO Britain would get involved ASAP, which might be later in 1915, at least forming a blockade of Germany, but not having troops to send until after the decisive battles in France in the first months of the war. IMHO the Ottomans stay neutral until later on, which means Russia gets more material support early on and longer. What would this version of WW1 turn out like?