The best guess for the populating of Greece is that people from Anatolia (modern Turkey) moved in around 1900 BCE. This theory is supported by ceramics which have been found dating from that period and from linguistic evidence. Another interesting question concerns the gold found in some ancient tombs in the area from that period of time. Gold is not natural to the area and no one knows where they would have gotten it.

(The Great Courses – Ancient Greek Civilization)