noun which may take the genitive case particle 'no'
prehistoric
Refers to the period before written records; used attributively with の.
Prehistoric ruins were discovered in this area.
Also means 'prehistoric', but is more technical and often used in academic contexts like 先史時代 (prehistoric era). 歴史以前 is a more descriptive, everyday term.
Compound of 歴史 (history) and 以前 (before, previous). The reading is the standard on'yomi combination.