During the 800's Jersey was plundered again and again. Houses and chapels were burnt down, and the Neolithic tombs were raided for treasure. These raids continued until 911 AD when France purchased peace with the Vikings. Political allegiance The Channel Islands remained politically linked to Brittany until 933, when they were seized and annexed to Normandy. For the next 270 years Jersey came under Norman rule. There is not a lot known about Jersey during these years, but the legal system set up by the Normans still exists today. Jersey remained part of the Anglo-Norman kingdom until 1204, when England lost Normandy to King Philippe Auguste of France. The islands chose to remain loyal to the English crown, and the king of England governed them as a separate entity. Military significance From 1204 onwards Jersey became an important military post between France and England. Mont Orgueil was built by the English as a Royal fortress and military base. There was great unrest in Jersey for the next 120 years, mainly because of political oppression and interference with the ancient customs of the island. The Hundred Years War & Wars of the Roses From 1337 to 1453 England and France were at war, and because of its position Jersey was exposed to constant attacks. It was even occupied during 1380. Grosnez Castle was probably built about this time, but was merely a moat, a gatehouse and a wall. Once the Hundred Years War had ended, Jersey had a brief respite of peace for 2 years. But in 1455 the Wars of the Roses flared up. The war lasted until 1484, and Jersey was once again occupied - this time for seven years, until England reclaimed the island in 1468.
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