Hmm, for the first one, I can't really say. It's possible that Japan could have ended up as a more united country than it would have been if otherwise, but hmm...
For the second one, I'd need a little more information. Did it stave off all of the barbarian hordes? Did the west and east stay united?
Run with the idea that the Roman Empire remained strong centrally, and that the office of emperor was eventually bound by laws so that the emperor could be disposed if he were an idiot like say, Commodus.
Now, if Nobunaga had survived, Japan would've likely seen a vicious and despotic shogunate for longer than if Tokugawa and Toyotomi hadn't started their civil war.
More technological advances maybe? I kinda think if Rome had survived there wouldn't have been a dark age; or at least it would have been much smaller. imo...
Oh and modern day Italy(if there would be one; maybe would be called by another name) would end up with some nice land. Think about how different Catholicisim could have been too.
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"Jesus also thought that non-believers should be stoned"------Alliance
this has always struck me as an interesting question. Certainly the fall of teh Roman empire didn't do too much to effect the spread of christianity, but what people in certain groups always want to say is that the fall of teh Roman empire came about because of their inherent divious behavior. But, it was ultimately christianity that led to teh fall of the Roman empire.
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Not keen on Japanese History, so I can't pretend I'm an expert.
As far as Roman Empire goes - perhaps the geography of what we know as ''Europe'' would be very different.
Perhaps we would all be 'Romans' right now, and a major power in the world.
Perhaps Native Americans would still be where they are, or perhaps we would have invaded America and made a second Rome there.
And while all this is happening Greece would be the most bitter country in the world.
Empire would have eventually fallen though. All Empires do.
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في هذا العالم ثلاثة أشخاص أفسدوا البشرية : راعي غنم , طبيب و راكب الجمال , و راكب الجمال هو أسوأ نشال و أسوأ مشعوذ بين الثلاثة