This scenario is based on a prolonged US Civil War- a more defensive confederacy holds off the Union longer, while less dramatic Union losses kept public morale up long enough for the Union to win the war in the end. This ends up impacting the outcome of the Austro-Prussian war, as the US Civil War served as a sort of testing ground for new military technologies and tactics, resulting in Austria adjusting their tactics and adopting the bolt-action rifle earlier- the war ends in a sort of stalemate, after Austrian forces reclaim Silesia but the rest of Germany falls to Prussia. A few other fun points, the Mexican Empire under Maximilian survives, America becomes essentially an elective monarchy, and there is no WW1 but crisis in the Balkans turns into a pan-European war that ends in the collapse of the Ottomans. Most recently, China has just been divided into spheres of European influence and Japanese influence, after the second Russo-Japanese War.