The year is 1347. In OTL, the Bubonic Plague or the Black Plague ravages Europe, killing 30 to 50% of its population. In this timeline, the Pope has forbid all trade with the east including the Byzantine Empire which probably exported the disease via China. The Pope disapproves of the Orthodox brand of Christianity practiced by the Byzantines. Europe as a result avoids the Black Death. This, of course, results in a very different world as we know it.
1351 The Moors begin an all out offensive from their stronghold in Spain against the French.
1352 The English decide to end their war with France and ally with them against the Moors in the name of Christendom. Other Christian nations follow: Holy Roman Empire, Aragon, Castile, Scotland, Holland, Austria and all of Italy. This war was to last 18 years.
1356 The Byzantine Empire falls on hard times because of the halt of trade with western Europe. Small outbreaks of plague occur in eastern Syria.
1359 The Turks sack Constantinople almost 100 years earlier in OTL. The emperor flees to Athens, Greece. The Turkish sultan cuts a deal with the Byzantines, allowing them to keep Greece while the rest of the empire is handed over to the Turks.
1370 Euro-Moor war ends in victory for the European allies. The Moors exit Spain 120 years earlier than OTL. Europe, as result of no Plague, has the manpower to win this conflict.
1373 Aragon, Castille and Grenada unite to form Spain.
1382 England, France, Spain, Holy Roman Empire, Greece and the Italian city-states unite to form the United European Empire or Europa. The Emperor position rotates between the Kings of the member nations every four years. The King of France was chosen first, Greece second, England third, Italy fourth, Holy Roman Empire fifth, Spain sixth. This was done to prevent any member nation from usurping power in the empire. Europa was formed to counter the Ottoman Turkish threat from the East.