Harris Tweed (Clò Mór or Clò na Hearadh in Gaelic), is a luxury cloth that has been handwoven by the islanders on the Isles of Harris, Lewis, Uist and Barra in the Outer Hebrides of Scotland, using local wool.
Traditional Harris Tweed was characterized by subtle flecks of color achieved through the use of vegetable dyes, including the lichen dyes called "crottle" (Parmelia saxatilis and Parmelia omphalodes which give deep red- or purple-brown and rusty orange respectively). These lichens are the origin of the distinctive scent of older Harris Tweed.
The original name of the cloth was tweel, the Scots for twill, the cloth being woven in a twilled rather than a plain pattern. A traditional story has the current name coming about almost by chance. About 1830, a London merchant received a letter from a Hawick firm about some tweels. The London merchant misinterpreted the handwriting understanding it to be a trade-name taken from the name of the river Tweed which flows through the Scottish Borders textile areas, subsequently the goods were advertised as Tweed, the name has remained so ever since.
With the initiation of the industrial revolution the Scottish mainland turned to mechanisation, but the Outer Hebrides retained their traditional processes of manufacturing cloth. Until the middle of the 19th century the cloth was only produced for personal use within the local market. It was not until between 1903 and 1906 that the tweed-making industry in Lewis significantly expanded. Production increased until the peak figure of 7.6 million yards was reached in 1966.