Great Vanishing
The Great Vanishing is a major event that occurred between approximately 1800 BCE and 800 BCE, and primarily impacted eastern Aurora but had continent-wide effects. The event itself, though not widely understood, marked a shift in the cultures of eastern Aurora in the form of a great tragedy or disaster that brought about the downfall of the major civilizations of the Chalcolithic Period. Theories abound as to what may have caused the Great Vanishing, from a devastating war to a great drought, or a combination of various events and natural occurrences.
Theories
Although there are a number of theories that attempt to explain our lack of knowledge of this period of time, most do not have significant enough clout to be seriously considered in a scientific sense. The Drought and Great War Theories, though being the most likely and well-documented of the theories, are not entirely exclusive of each other. It is often argued that both could have happened simultaneously, and it is possible the war itself was caused by the lack of water forced on by the drought. Significant evidence from the Melit'hasa elven culture in the central Auroran Desert is vital to our knowledge on possible happenings during that time, although are not in and of themselves considered hard evidence of historical events. Archaeological discoveries within the desert are often used in conjunction with the Melit'hasa stories to understand what may have happened prior to the Great Vanishing.
Laqytian civilisation in western aurora also fell during the vanishing, although in the aftermath a significant amount of extant written material was lost and so evidence of a connection is sparse. Changes in the local climate and natural disasters are hinted at, although it has also been suggested that a weakening trade following the fall of other civilisations in the far east may have indirectly weakened the city states well before its fall. Invaders are also mentioned as the cause for several Laqytian cities suffering significant damage during this period, and these may have been from the far east. However genealogical studies offer little support to that theory though.
Drought Theory
The drought theory primarily attests to the shift in climate that often occurs within the Great Auroran desert as a result of the shifts in the temperature oscillations that occur in the Cerenerian Ocean. It is believed a series of uniquely extreme climatic shifts occurred in succession of each other during the 21st Century to the 19th Century BCE, forcing the cultures of the time to resort to reverting their habits back to one of a hunter-gatherer society. This is partially backed by the oral stories taught in the Melit'hasa cultures of the central desert, mentioning a period where "generations abandoned their great towers of stone, as the water had run dry."
Great War Theory
The Great War theory attests that a significant civilization-destroying war befell the civilizations of the Chalcolithic Era, forcing them back into the Stone Age technologically. Many murals on ruins found buried under the Great Auroran Desert often depict battles not accounted for in our modern understanding of history, and as such historians and archaeologists alike place these murals as possible evidence of a devastating war. Stories passed down by the Melit'hasa also mention a major war that their people suffered long ago in their cultural history.