It is said that in AD 709 a storm washed away the strip of land which connected the island with Herm.
In 1416, it became part of Henry V's estate and still remains a Crown lease, now owned by the States of Guernsey.
From 1920 to 1923 it was leased by Compton MacKenzie along with Herm and remained part of that estate for a number of years.
From September 1964 until December 1971 the island was occupied by the Faed family: Angus Faed, his wife Susan and their four children. Susan Faed was the 22nd tenant of Jethou.
It is flanked by two islets, Crevichon to the north and Fauconniere to the south. There is one house on the island and two cottages, as well as a large garage.
It is now leased by Sir Peter Ogden.
Jethou is administered entirely by the States of Guernsey and elects members as part of the St Peter Port South electoral district.