The sacking of Smyrna was certainly the biggest (and Smyrna at the time was very large city, probably with the greatest concentration of Greeks outside Athens itself) and the harbour scenes with people trying to get to the ships were well documented. But the Pontos area with cities like Samsun, Trabzon and Surmene held the descendants of the 10,000 soldiers whose arrival there was documented by Xenophon, who over the centuries must have grown to a sizeable number. Certainly today, it seems to me that more people refer to themselves as being of Pontian rather than Asia Minor descend (but I have no stats to back this, it's just a qualitative observation).

Even my long post above was not enough to mention all relevant details, of course. The "pristine Greek" language was the isolated Pontian's of course, while those from the Med coast or the Anatolian plateau were using quite a lot of Turkish (indeed, some even exclusively). Many of the latter, when expelled from Turkey in 1922 couldn't understand why - they spoke Turkish and felt like Turks. Sure, they had Greek surnames and were Christians, but no less Turks for that, in their own minds. Their great-great-great grandparents were buried in their villages; why did their own country no longer recognise them?

The Pontians specifically brought across their own music and dances, again the closest thing to the ancient greek equivalent we have today, because of that isolation - it was the Med and Istanbul Greeks that brought the zeibekikos and other rhythms that resulted in rebetiko; however, by that time all refugees were (incorrectly) referred to as Pontians, so things got confused.

There is a wonderful book written about those times and about the rise of Kemal Ataturk (a most amazing individual that is still revered throughout Turkey, and rightly so) and the creation of the Turkish Republic. It is Birds Without Wings (2004) by Louis de Bernieres, shortlisted for the 2004 Whitbread Novel Award and it cuts through the propaganda of both sides to the real events and feelings among the ordinary people.

It is amazing to think that all those events and the forced re-mixing of populations (and the cultural output that resulted from it) are less than 100 years old - which is why "rebetiko" is not considered "traditional"; it certainly can't compete in terms of age with some of the mainland songs and tunes that are easily 2-300 years old.