It is 285 AD and the Roman Empire doesn't split. Instead, it stays together. Barbarians invade the empire but still lose a lot of territory. As a result, the The nations of France, England and Spain, and other Western European countries form but the Romans still have a hold on OTL modern day Greece, Italy, Croatia, Bulgaria, and Rome's Eastern European holds. The Arab invasions still occur but take over only OTL modern day Iraq, Syria, Israel, and Lebanon. After failures in the old world, they begin to set up colonies in America by 750 AD and spread Christianity in a similar fashion as the Conquistadors did in OTL in the 1500s. Also, they occupy most of Africa by 1450.