THE MINOAN COLLAPSE
Between 1935 and 1939, Greek archaeologist Spyridon Marinatos posited the Minoan eruption theory. An eruption on the island of Thera (present-day Santorini), about 100 kilometers (62 mi) from Crete, occurred during the LM IA period (1550–1500 BC). Some place the date of the eruption a century earlier in the 17th century BC.
One of the largest volcanic explosions in recorded history, it ejected about 60 to 100 cubic kilometers (14 to 24 cu mi) of material and was measured at 7 on the Volcanic Explosivity Index. The eruption devastated the nearby Minoan settlement at Akrotiri on Santorini, which was entombed in a layer of pumice.
Although it is believed to have severely affected the Minoan culture of Crete, the extent of its effects has been debated. Early theories proposed that volcanic ash from Thera choked off plant life on the eastern half of Crete, starving the local population; however, more-thorough field examinations have determined that no more than 5 millimeters (0.20 in) of ash fell anywhere on Crete.
Based on archaeological evidence, studies indicate that a massive tsunami generated by the Thera eruption devastated the coast of Crete and destroyed many Minoan settlements. Although the LM IIIA (late Minoan) period is characterized by affluence (wealthy tombs, burials and art) and ubiquitous Knossian ceramic styles, by LM IIIB (several centuries after the eruption) Knossos' wealth and importance as a regional center declined.
Significant remains have been found above the late Minoan I-era Thera ash layer, implying that the Thera eruption did not cause the immediate collapse of Minoan civilization. The Minoans were a sea power, however, and the Thera eruption probably caused significant economic hardship. Whether this was enough to trigger a Minoan downfall is debated. Mycenaean Greece conquered the Minoans during the late Minoan II period, and Mycenaean weaponry has been found in burials on Crete soon after the eruption.
Many archaeologists believe that the eruption triggered a crisis, making the Minoans vulnerable to conquest by the Mycenaeans. According to Sinclair Hood, the Minoans were most likely conquered by an invading force. Although the civilization's collapse was aided by the Thera eruption, its ultimate end came from conquest. Archaeological evidence suggests that the island was destroyed by fire, with the palace at Knossos receiving less damage than other sites on Crete. Since natural disasters are not selective, the uneven destruction was probably caused by invaders who would have seen the usefulness of preserving a palace like Knossos for their own use.
Several authors have noted evidence that Minoan civilization had exceeded its environmental carrying capacity, with archaeological recovery at Knossos indicating deforestation in the region near the civilization's later stages.