Prehistory

Prehistory means literally "before history", from the Latin word for "before," præ, and Greek ιστορία. Human prehistory is the period from the time that behaviorally and anatomically modern humans first appear until the appearance of recorded history following the invention of writing systems. Since both the time of settlement of modern humans and the evolution of human civilisations differ from region to region, prehistory starts and ends at different moments in time, depending on the region concerned.

Sumer in Mesopotamia, the Indus valley civilisation and ancient Egypt were the first civilisations to develop their own scripts, and to keep historical records; this took place already during the early Bronze Age. Neighbouring civilisations were the first to follow. Most other civilisations reached the end of prehistory during the Iron Age.

The beginning of written materials (and so the beginning of local "historic times") varies; in many cultures, especially outside Eurasia, it follows conquest by a culture with writing, and often the earliest written sources on pre-literate cultures come from their literate neighbours. The period when a culture is written about by others, but has not developed its own writing is often known as the protohistory of the culture.

By definition, there are no written records from human prehistory, so dating of prehistoric materials is crucial. Clear techniques for dating were not well-developed until the 19th century.

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