Sapiento - this is very interesting. And a great looking map.

A few minor comments (sorry I have only just come across this project):

  • you might consider removing from the map the twentieth century man made dams: e.g. Aswan on the Nile and the various dams on the Blue Nile, Euphrates and Tigris Rivers, which I expect would not exist in 1500 AD in your alternative universe;
  • also, is Persepolis correctly located near the Shatt Al-Arab waterway? The great Persian city of Persepolis was further inland and close to Shiraz - I note you have a second unnamed town marker in that vicinity; and
  • I could not find the city of Antioch in the region of that name, which I would think should be included unless something happened to it in your alternative universe (a la Carthage), then perhaps it should be shown as a ruin? Recall that Antioch was one of the 5 Patriarchates of the Later Roman Empire (along with Rome, Alexandria, Jerusalem and Constantinople, giving some indication of its importance in that Empire). 1,000 years later in your alternative non-Roman universe, no doubt things have changed significantly. I understand that Antioch has suffered devastating earth quakes during that period.

Are you planning to do a companion map of Europe as at 1500 AD in your alternative universe? That would be a fascinating exercise: no Arabic Islamic expansion in North Africa, Sicily and Spain - the Visigothic kingdoms in Spain and the successor states of the Vandals/Byzantium in North Africa would have survived and maybe flourished. Would they have proved to be a counter weight to the Franks in Italy and beyond? Would the pope have crowned one of these princes as the Western Emperor instead of Charlemagne in 800 AD? And of course no crusades, unless the Latins considered the Mongol brand of Christianity heretical and sought to take back the Holy Places from them (entirely possible). I could go on....!