Prehistory

Prehistory, also called pre-literary history, is the period of human history between the first known use of stone tools by hominins c. 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared c. 5,200 years ago. It took thousands of years for writing systems to be widely adopted, with writing having spread to almost all cultures by the 19th century. The end of prehistory therefore came at different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. It is based on an old conception of history that without written records there could be no history. The most common conception today is that history is based on evidence, however the concept of prehistory has not been completely discarded.

In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilisation, and ancient Egypt were the first civilizations to develop their own scripts and keep historical records, with their neighbours following. Most other civilizations reached their end of prehistory during the following Iron Age. The three-age division of prehistory into Stone Age, Bronze Age, and Iron Age remains in use for much of Eurasia and North Africa, but is not generally used in those parts of the world where the working of hard metals arrived abruptly from contact with Eurasian cultures, such as Oceania, Australasia, much of Sub-Saharan Africa, and parts of the Americas. With some exceptions in pre-Columbian civilizations in the Americas, these areas did not develop writing systems before the arrival of Eurasians, so their prehistory reaches into relatively recent periods; for example, 1788 is usually taken as the end of the prehistory of Australia.

The period when a culture is written about by others, but has not developed its own writing system, is often known as the protohistory of the culture. By definition, there are no written records from human prehistory, which can only be known from material archaeological and anthropological evidence: prehistoric materials and human remains. These were at first understood by the collection of folklore and by analogy with pre-literate societies observed in modern times. The key step to understanding prehistoric evidence is dating, and reliable dating techniques have developed steadily since the nineteenth century. The most common of these dating techniques is radiocarbon dating. Further evidence has come from the reconstruction of ancient spoken languages. More recent techniques include forensic chemical analysis to reveal the use and provenance of materials, and genetic analysis of bones to determine kinship and physical characteristics of prehistoric peoples.

The beginning of prehistory is normally taken to be marked by human-like beings appearing on Earth. The date marking its end is typically defined as the advent of the contemporary written historical record.

Both dates consequently vary widely from region to region. For example, in European regions, prehistory cannot begin before c. 1.3 million years ago, which is when the first signs of human presence have been found; however, Africa and Asia contain sites dated as early as c. 2.5 and 1.8 million years ago, respectively. Depending on the date when relevant records become a useful academic resource, its end date also varies. For example, in Egypt it is generally accepted that prehistory ended around 3100 BCE, whereas in New Guinea the end of the prehistoric era is set much more recently, in the 1870s, when the Russian anthropologist Nicholai Miklukho-Maklai spent several years living among native peoples, and described their way of life in a comprehensive treatise. In Europe the relatively well-documented classical cultures of Ancient Greece and Ancient Rome had neighbouring cultures, including the Celts and the Etruscans, with little writing. Historians debate how much weight to give to the sometimes biased accounts of these protohistoric cultures found in Greek and Roman literature.

In dividing up human prehistory in Eurasia, historians typically use the three-age system, whereas scholars of pre-human time periods typically use the well-defined geologic record and its internationally defined stratum base within the geologic time scale. The three-age system is the periodization of human prehistory into three consecutive time periods, named for their predominant tool-making technologies: Stone Age, Bronze Age and Iron Age. In some areas, there is also a transition period between Stone Age and Bronze Age, the Chalcolithic or Copper Age.

For the prehistory of the Americas see Pre-Columbian era.

The notion of "prehistory" emerged during the Enlightenment in the work of antiquarians who used the word "primitive" to describe societies that existed before written records. The word "prehistory" first appeared in English in 1836 in the Foreign Quarterly Review.