Complex sentence: Of Alexander Sutherland who was executed, "Kilphedder" was the place of his residence, and his descendants, occupied the lands for generations on payment of a merely nominal rent to the Earls of Sutherland.
Split into simpler sentences: Of Alexander Sutherland who was executed, his place of residence was known as "Kilphedder". His descendants, occupied the lands for generations on payment of a nominal rent to the Earls of Sutherland.