From Lyons in Eure in Normandy.
The earliest records of the name in Scotland are to be found in Restenneth near Forfar in 1321 in the persons of Johannes filius Leonis and Hugo filius Leonis.
Twenty years later John Lyon had a charter of the lands of Forteviot and Forgandenny near Perth. Sir John Lyon, chamberlain of Scotland in the late 14th century, was granted lands at Glamis by Robert II; one of his descendants was created Earl of Kinghorn in 1606, the title later being changed to Kinghorn and Strathmore, and the family name to Bowes-Lyon.
Queen Elizabeth the Queen Mother is a daughter of the 14th earl of Strathmore.
There is a tradition that some of the Glamis tenantry followed the clannish practice of adopting the lairds surname.
Robert Lyon, a local Episcopal clergyman, became chaplain to Lord Ogilvies regiment in the ’45 and was executed for treason in 1746.
The name was also very common in Ireland.
“Scottish Surnames” by Collins