What would have happened if Germany hadn't declared war on Russia, which would have meant that Austria-Hungary would have needed to fend for herself, in turn causing no WW1? (which in turn means no WW2).
It's 1914, July Crisis. The world is on the brink of war over the assassination of Franz Ferdinand. The world gasps when Serbia refuses to do all ten of the demands the ultimatum has. Austria-Hungary, almost, almost surely backed by Germany, cuts the last string of peace and invades Serbia. However, to her horror, Germany refuses to help, afraid a war with Russia would give France an excuse to re-take their territory of Alsace-Lorraine. Germany scrambles to retain good relations and even elevates French as a co-official language in the Imperial Territory. France continues to make relations better by offering a few resources. Meanwhile, Austria-Hungary imposed martial law into Bosnia and Herzegovina, and Russia advances into Galicia and Transylvania.