By the early 1860s, as summarized in Charles Lyell's 1863 book Geological Evidences of the Antiquity of Man, it had become widely accepted that humans had existed during a prehistoric period—which stretched many thousands of years before the start of written history.
Pada awal 1860an, sesuai dengan yang dijelaskan dalam buku 1863 Charles Lyell Geological Evidences of the Antiquity of Man, banyak orang menerima bahwa manusia telah ada pada zaman pra-sejarah—yang terbentang beberapa ribu tahun sebelum permulaan sejarah tertulis.