Principal Mycenaean sites in Greece. The Mycenaean civilization flourished during the period roughly between 1600 BC, when Helladic culture in mainland Greece was transformed under influences from Minoan Crete, and 1100 BC, when it perished with the collapse of Bronze-Age civilization in the eastern Mediterranean. The collapse is commonly attributed to the Dorian invasion, although other theories describing natural disasters and climate change have been advanced as well. The major Mycenaean cities were Mycenae and Tiryns in Argolis, Pylos in Messenia, Athens in Attica, Thebes and Orchomenus in Boeotia, and Iolkos in Thessaly. In Crete, the Mycenaeans occupied Knossos. Mycenaean settlement sites also appeared in Epirus,[2] Macedonia,[3] on islands in the Aegean Sea, on the coast of Asia Minor, the Levant,[4] Cyprus and Italy. Mycenaean artifacts with Linear B inscriptions have been also found as far away as Germany,Mycenaean swords as far away as Georgia in the Caucasus[10] and Mycenaean bronze double axes and other objects dating from 13th century BCE have been found in Ireland and in Wessex and Cornwall in England.