The Kilt had its start as a "belted plaid" in the Scottish Highlands of the 16th century, and was worn in much the same way as the Great Kilt.
The Highlanders could use the plaid as both a warm garment and a blanket to protect them against the cold of the moors. In the 18th century, the more convenient "little kilt" was developed which separated the skirt and the shoulder drape.