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Why do Scottish people wear plaid?

Plaid is fabric woven into a pattern called a tartan, and tartans pertain to specific family groups called clans. In Scotland, people wear tartans to show kinship with, or to honor a clan.
The identification of specific tartans to Highland clans only occurred at the beginning of the 19th century following a romantic revival. Prior to this tartan was produced in a region and worn by anyone in the locality whatever their clan and some of them were just numbered. They are generally only worn on formal occasions.

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