The origin of this name is doubtful, but it may be derived from the Gaelic Fearsithe, meaning "Man of peace". A Forsyth (to use the modern spelling) was given land at Sauchie, Stirlingshire, by King Robert I, about 1306, and in 1368 a Forsyth was Constable of Stirling Castle. This surname was not confined to the Stirling district and at an early date is found in widely separated places such as Edinburgh, Dumbarton and Inverness. In 1368 William de Fersith was a Baillie in Edinburgh.
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