So this board obviously has a lot of discussion on this general idea, so in large measure we're going over stuff we talked about before; we'll also be going with a pretty standard PoD, where the Ethiopian army reaches Mecca in 570 CE. The twist for this particular thread -- I want us to focus on just the geopolitical implications on the affected civilizations, only as far as 800 CE. So for example: How are the tribes of the Arabian peninsula affected by our PoD? How, in turn, does the Empire of Askum fare in this time? What of the Sassanids; do they last another 150 years or more? And what of the Eastern Roman Empire; do they hold together in this same time? How does the Visigothic Kingdom in Iberia fare during this time? Do the Franks still get their shit together in the 8th Century, or absent the threat of Muslim Spain, do they continue to squabble among themselves? Obviously there's no Muslim Conquest of Transoxiana, and thus no Battle of Talas; does this mean there's no An Lushan Rebellion in China? And if there's any other major affected regions I'm not thinking of (again, in the 570 to 800 CE period), let me know.* And with that -- let's do this again. *AIUI, Viking Expansion down the Volga was a 9th Century phenomenon, and so falls out of the purview of this thread.