William Sandeman (born Luncarty, Scotland 1722, died Perth, Scotland 1790) was a leading Perthshire linen and later cotton manufacturer. For instance in 1782 alone, Perthshire produced 1.7 million yards of linen worth £81,000. Linen manufacture became by the 1760s a major Scottish industry, second only to agriculture.William was born in 1722 in Luncarty just north of Perth, Scotland the fifth child of David Sandeman and his second wife Margaret Ramsay.