Prehistoric (pre-written) period of human history of Ireland covers the time from the appearance of the first people in it at the end of the last glaciation and to the early iron age, when Ireland was first mentioned in Greek and Roman sources. Since Ireland was geographically and historically a single cultural region, this article also examines the territory of present-day Northern Ireland as part of great Britain.Prehistoric (pre-written) period of human history of Ireland covers the time from the appearance of the first people in it at the end of the last glaciation and to the early iron age, when Ireland was first mentioned in Greek and Roman sources. Since Ireland was geographically and historically a single cultural region, this article also examines the territory of present-day Northern Ireland as part of great Britain.