During the Arab Muslim conquests, why did some peoples become Arabized while others didn't? For instance, why did Persians not come to be considered Arabs, whereas the people of much of North Africa did?

by ordurvs
diseased_oranguntan

The Middle East and North Africa were already populated by Semitic peoples speaking languages related to Arabic. The Berbers in North Africa are somewhat more distantly related to the Arabs, but the pre-Arab Egyptians were closer, and Carthage/Punic areas, being colonies of Phoenicia in Lebanon, also spoke languages close to Arabic.

Meanwhile Iran and areas further East spoke languages unrelated to Arabic or Semitic languages