Thucidetes mentions two major transfers of populations that took place after the Trojan War. One of them is the transfer of the tribe of the Dorians.
When we are talking about the Dorian invasion we are talking about the transfer of the specific tribe to the Peloponnese that was the center of the Mycenaean World. So, talking about an invasion of the Dorians in the Greek World is not quite accurate primarily because Dorians took shape as a tribe in Central Greece as the etymology of their name shows.
But let's take things from start.
Herodotus ( I, 56,3) locates the initial place of their settlement in Central Greece, in a plain that was located on the foot of Mt Olympus. From that place they were driven away by another tribe (Kadmeans) and they settled to the Northwestern part of Greece on the Mt Pindos where they took the name Makednoi (note that when all these happen they do not have the name Dorians).
The name Dorian:
<font face="symbol">Dvrieu</font>s
Doriefs in Greek is a national name as the suffix <font face="symbol">eu</font>s (-efs) demonstrates and the name in Greek shows that they were the habitants of a large area in Central Greece that is called Doris. <font face="symbol">Dvri</font>s
Now we know that Dorians were consisted of three different groups, all of them Greek speaking that around the year 1100 BC decided to transfer to the Peloponnese. This transfer was a military operation something that is illustrated by their myths (they are very complicated but if you insist...)
So the Dorians invadde the Peloponnese and they took over the major Mycenaean centers.
The first three centuries that followed the Dorian invasion in the Peloponnese are characterized by a low civilization standards. During this period new Palaces or walls are not built and we don't have traces of monumental Art.
The vaulted shaped burial chambers are abandoned to give their place to wedged-shaped graves.
Iron weapons appear as well and this is the reason why The Dorian Invasion is described as the Iron Age. This term was introduced in 19th ce but it's not in use any more. Also, in the Bibliography below you will see that the Dorian Invasion is described as “ Greece’s Dark Ages” by the time I studied Archaeology ( in the middle 90ies) this term wasn’t in use anymore.
Also we observe a change to the shape and decoration of the pottery. The Geometric Style in Art that symbolizes the beginning of the era of Reason is introduced and the new way of social organization, the city-state appears.
Basic Bibliography ( If you have access to a university Library you won’t have difficuly in finding the following books that are considered classics)
1.Desborough.V.,The Greek Dark Ages,1972
2.Daniel J.F.-Brooner O. The Dorian Invasion, A.J.A*, 1948,p.107-118
3.Snodgrass P, The Dark Ages of Greece, an archaeological survey of the 11th to the 8th ce.
* A.J.A Abbrev. for the American Journal of Archaeology.
