In the thirteenth century, the French pirate Eustace the Monk, having served King John, used Sark as a base of operations.
During the Middle Ages, the island was populated by monastic communities.
Ouen, on condition that a house was built and maintained on each parcel and that "the Tenant" provided one man, armed with a musket, for the defence of the island.
The 40 tenements survive to this day, albeit with minor boundary changes.
kingdoms until 933, when it became part of the Duchy of Normandy.
Following the Norman conquest of England in 1066, the island was united with the Crown of England.
This high point is named Le Moulin, after the windmill.
Recent (1990–2000) geological studies and rock age dating by geologists from Oxford Brookes University shows that the gneisses probably formed around 620–600 million years ago during the Late Pre-Cambrian Age Cadomian Orogeny.
The quartz diorite sheets were intruded during this Cadomian deformation and metamorphic event.
By the 16th century, however, the island was uninhabited and used by pirates as a refuge and base. Ouen in Jersey, received letters patent from Queen Elizabeth I granting him Sark as a fief in perpetuity on condition that he kept the island free of pirates and occupied by at least forty men who were of her English subjects or swore allegiance to the Crown.
This he duly did, leasing 40 parcels of land (known as "Tenements") at a low rent to forty families, mostly from St.