This text offers a full-scale examination of the out-movement of migrant Highlanders from the Highlands to the urban Lowlands in the 18th and 19th centuries and of the migrant culture of urban Gaels within this new urban context. It follows work by the author on the historical geography of the Gaedhealtachd, the Gaelic-speaking areas of Scotland. The author demonstrates through the use of maps, tables and detailed archival analysis how, at what time, and in what numbers Highlanders moved to the Lowlands, what cultural expression they gave to their new Lowland location and to the development of a Gaelic migrant culture in the towns and cities of urban Lowland Scotland.