Arabization
Arabization describes a growing cultural influence on a non-Arab area that gradually changes into one that speaks Arabic and/or incorporates Arab culture. It was most prominently achieved during the 7th century Arabian Muslim conquests which spread the Arabic language, culture, and—having been carried out by Arabian Muslims as opposed to Arab Christians or Arabic speaking Jews—the religion of Islam to the lands they conquered. The result: some elements of Arabian origin combined in various forms and degrees with elements taken from conquered civilizations and ultimately denominated "Arab", as opposed to "Arabian".
Read more about this topic: Islamization, History