And here is the map of the early Islamic expansions:
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Tell me, boy, how do you think Arabic language and culture went from being local to a small corner of a desert to being spoken by a continent?
Allow me to give you a taste of the answer: consider this description of the typical modus operandi of Islam by the great "scholar of the Islamic Golden Age," Al-Biruni:
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"When Qutaibah bin Muslim under the command of Al-Hajjaj ibn Yusuf was sent to Khwarazmia with a military expedition and conquered it for the second time, he swiftly killed whoever wrote the Khwarazmian native language that knew of the Khwarazmian heritage, history, and culture. He then killed all their Zorastrian priests and burned and wasted their books, until gradually the illiterate only remained, who knew nothing of writing, and hence their history was mostly forgotten."
Note that Al-Biruni himself was a native Khwarazmian and he here is describing how his people were converted to the Arabic religion of peace.
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Trust me boy, I don't need to told anything about history, or anything by someone on your league of cognition since I could learn more about your own history in a month or two than you could learn in a life-time.