The Thirty Years’ War was about as close to a world war as you could reasonably get before colonialism and industrialization really got off the ground. I know it’s a boring answer, but this is pretty much OTL.Would it be possible for an alternate Protestant Reformation to trigger a World War?
Not a boring answer. The Thirty Years' War was the closest thing to an apocalyptic total war that had occurred up to that point, with the exception of maybe the Mongol invasion of the Middle East.The Thirty Years’ War was about as close to a world war as you could reasonably get before colonialism and industrialization really got off the ground. I know it’s a boring answer, but this is pretty much OTL.
You could in theory make the Thirty Years' War even bigger than it was in OTL by having a few key changes. Get the Ottomans to invade Austria and then get the Safavids to invade the Ottomans. Bring Poland-Lithuania against the Turks and get Russia to attack the Poles. From there get Indian states against the Safavids and each other, bringing basically the whole subcontinent to war. And for good measure, keep China in civil war for longer and perhaps get Japan to invade Korea again, with Dutch assistance while the Spanish assist Korea. With that, you get almost a World War. The only major areas left almost untouched by this über war are Africa, the Americas, and Australia.The Thirty Years’ War was about as close to a world war as you could reasonably get before colonialism and industrialization really got off the ground. I know it’s a boring answer, but this is pretty much OTL.
I'd say Mughals over just Indian states. They were in conflict with both Safavids and Portuguese during the early half of the 1600s and were friendly with the Ottoman Empire. Just have those conflicts escalate and bring in more of India. It's doubtful that Japan would be inclined to attack Korea again, not so soon after being repelled and the Hideyoshi clan overthrown (I recall reading that the Tokugawa built coastal defenses in fear of Ming-Joseon retaliation). Plus the Tokugawa were cordial with the Joseon and reestablished trade relations less than a decade after the war so you'd probably need someone other than Ieyasu take over. But, in the case of a second (technically third) Japanese invasion, the Manchu Qing would probably intervene, seeing as the Joseon were either friendly (Gwanghaegun) with the Qing or a direct vassal (Injo). So you might see the Ming stay around for a bit longer while the Qing deal with the Japanese.You could in theory make the Thirty Years' War even bigger than it was in OTL by having a few key changes. Get the Ottomans to invade Austria and then get the Safavids to invade the Ottomans. Bring Poland-Lithuania against the Turks and get Russia to attack the Poles. From there get Indian states against the Safavids and each other, bringing basically the whole subcontinent to war. And for good measure, keep China in civil war for longer and perhaps get Japan to invade Korea again, with Dutch assistance while the Spanish assist Korea. With that, you get almost a World War. The only major areas left almost untouched by this über war are Africa, the Americas, and Australia.