Scotland during the Roman Empire of the geography of Scotland had extended to the "Hebudes" (The Hebrides), "Dumna" (probably the Outer Hebrides), the Caledonian Forest, and the Caledonians. Ptolemy, possibly drawing on earlier sources of information as well as more contemporary accounts from the Agricolan invasion, identified 18 tribes in Scotland in his "Geography", but many of the names are obscure. His information becomes much less reliable in the north and west, suggesting early Roman knowledge of these area was confined to observations from the sea. Famously, his coördinates place most of Scotland north of Hadrian's Wall bent at a right angle, stretching due eastward
Scotland during the Roman Empire as unified ideas until centuries later. In fact, the Roman Empire influenced every part of Scotland during the period: by the time of the Roman withdrawal from Britain around 410, the various Iron Age tribes native to the area had united as, or fallen under the control of, the Picts, while the southern half of the country was overrun by tribes of Romanized Britons. The Scoti (Gaelic Irish raiders) who would give Scotland its English name, had begun to settle along the west coast. All three groups may have been involved in the Great Conspiracy that overran Roman Britain in