The Picts were a tribal confederation of peoples who lived in what is today eastern and northern Scotland during the Late Iron Age and Early Medieval periods. They are thought to have been ethnolinguistically Celtic. Where they lived and what their culture was like can be inferred from the geographical distribution of brochs, Brittonic place name elements, and Pictish stones. Picts are attested to in written records from before the Roman conquest of Britain to the 10th century, when they are thought to have merged with the Gaels. They lived to the north of the rivers Forth and Clyde, and spoke the now-extinct Pictish language, which is thought to have been related to the Brittonic language spoken by the Britons who lived to the south of them.