I wonder why did the Arabic culture, which was not nearly so widespread before the expansion of the Rashidun Caliphate, become dominant so quickly in the Middle East. Where were the Assyrians, Babylonians, Akkadians, Egyptians. Did those ancient peoples get assimilated in the Roman Empire and Persia already? Why did the Persians put up a bigger resistance than other ethnicities after being conquered by Arabs? How come so many different nations which existed in the Middle East suddenly disappeared ( Hittites, Hattites, Hurrians, Amorites etc. )
The Iranid cultures survived pretty well otherwise all Middle Eastern Islamified cultures adopted Arabic and Arab identity.
I'm a Christian from northern Iraq and our identity hasn't changed since we converted to Christianity shortly after Christianity was introduced. Our language is Syriac which comes from Aramaic. We're the closest descendants to Assyrians considering our location and are a genetically distinguishable ethnic group. I'm not sure why the ancient civilisations disappeared but I imagine it had to do with assimilation methods by large new empires, the introduction of religion which made people leave their pagan culture and large military defeats which ended empires.