[adrian_b]

Yes, while I agree with most of the criticism about the movie, that sentence has also stricken me as incorrect.

It is not known who the "sea people" were, e.g. whether they were invaders coming from far away or they were just some poorer local populations that had revolted in a time of famine, but what is known for sure is that a lot of cities around the Eastern Mediterranean have been destroyed and burned during several decades, and this has resulted in the disappearance of several centralized kingdoms, leaving only a few surviving big states, i.e. Egypt, Babylonia and Assyria, while everywhere else no central authorities remained and the territories were fragmented into small independent parts, consisting mostly of a city and its neighborhoods.