Late Bronze Age Shipwreck Excavation
nauticalarch.org
nauticalarch.org
The Late Bronze Age was a fascinating time around the Mediterranean; there was extensive trade between Egypt, the Hittites, Minoans, Assyrians, Mitanni, and others; shades of "globalization" and a multi-cultural aesthetic had emerged, then it all came crashing down in the 12th century BCE.
[1] https://www.amazon.com/1177-B-C-Civilization-Collapsed-Turni...
I recommend his 1h youtube talk about the bronze age & genesis of "1177 BC": https://www.youtube.com/watch?v=hyry8mgXiTk
Just to add to what you said, the part of the Bronze Age collapse that was specific to Greece has been dubbed, the "Dorian Invasion".[0]
After the Dorian Invasion, the culture and languages/dialects in Greece were replaced by those prevalent in Classical Greece, the era of Greece most people think of when referring to "Ancient Greece".
Although conquest could be one such way of spreading culture, it's generally more by intermarriage than displacement (e.g. see the saxon and normandy invasions of britain or the romanization of gaul).
My point being: the pre Dorian culture remained in Greece as well. The Mycenaeac influence was still visible in the literature of the day as a distinct culture; there was no clear attempt to impose a foreign culture by violence or other aggressive means. Or at least no evidence. Of course, we might know more if we ever get Linear B, but who knows if we ever will.
This is all a very long winded way of saying "invasion" doesn't ever really capture the subtleties of cultural diffusion. Ghengis conquered much of the Middle East, but the resulting cultural change was both more visible in places Ghengis never saw such as Western Europe and it was driven more by trade than by direct imposition.
1952, Ventris:
http://www.cam.ac.uk/research/news/cracking-the-code-the-dec...
"Ventris was able to show, ever more clearly over the months that ensued, that the language behind the script was Greek – in his own words “a difficult and archaic Greek, but Greek nevertheless”."
The Foundation series by Asimov talk about the Foundation, that aimed to hasten and then control a still inevitable collapse, and ensure itself would be the replacement culture.
Al Qaeda, that can mean "The Foundation" in Arabic, is speculated to have this aim too, using immigration, intermarriage, and dragging western civilization in a extended unpayable war with the same idea: hasten the inevitable collapse, and be ready to rebuild and replace from the ashes. (And ISIS is an impatient Al Qaeda, and wants to trigger a total war, to overextend western countries even faster, and cause a refugee-driven diaspora)
How many divers did they lose?