I live in the island of Yell.
There has been in existence for many years, the name of Dalziel, pronounced Deyell. It is thought that the name means from Yell.
From this the names of Diel and, of course Yell could be derived.
Before the middle of the 16th century surnames were often the names of where the person lived. This practise was especially prevalent in Norway, a land to which these islands have very close historical links.