The first language known here is the Akkadian which corresponds to it the Ebly language in Syria, which could also be Akkadian after all. Yes, there is a big similarity between all of them. They are also called Western Aramaic and Eastern Aramaic, and here we could also add the Arabic language, Hebrew, Ethiopian, and other languages. It s one family. Those peoples are of similar origins or same origin eventually, of course, all the holy books of different religions talk about the same origin for Mankind.
Science also tries to speak about same origins.
Even among those who migrated abroad. If you go to Detroit or Chicago or Australia or Melbourne, you ll see those Easterns or Chaldeans or Assyrians, those Christians speaking this language. Yes, majority, but not all. As we said majority of them live in the Arab world, consequently, Arabic is wide spread among majority of them as the language of literature and correspondence. This also what happened as a civilization belonging after the flourishing of the Arab civilization.