.. the Scots at Largs, in 1263, might have combated the Norwegians under the protection of Saint Margaret, and hence, possibly, the origin of the name Margarets-Law, given to the large cairn near Haily House,—given evidently in comparatively modern times, and that by a local population, under a mistaken belief, which yet continues, that the Norwegian dead (those who fell through the agency of St. Margaret) were interred within it.
In Notes and Queries, July 5th 1873. It all sounds a bit confused, especially when you see that there are a number of Margarets around in history c. the battle at Largs, on both sides.