The history of Guernsey dates to prehistoric times, with evidence of Neolithic occupation and later Roman occupation. Tradition credits Saint Sampson with introducing Christianity to the island.
Guernsey became part of the Duchy of Normandy and remained under the rule of William the Conqueror after he became king of England. In subsequent centuries, warfare and attacks by pirates and naval forces disrupted trade and prompted the construction of fortifications and the establishment of the Guernsey militia. After mainland Normandy came under French control in the thirteenth century, Guernsey remained under the English Crown.
During the English Civil War, most of Guernsey supported the Parliamentarians, while the garrison of Castle Cornet supported the Royalists. Privateering and maritime trade contributed to the island's prosperity during the Napoleonic Wars. Quarrying, horticulture, and tourism subsequently became important industries, while English gradually displaced Guernésiais as the principal language.
Guernsey was occupied by German troops during the Second World War. In the post-war period, its economy was rebuilt around tourism, agriculture and trade, followed by the growth of the finance industry.
Prehistory
Around 6000 BC, rising sea levels separated Guernsey from continental Europe as the English Channel formed. Neolithic farmers subsequently settled on the island and constructed dolmens and menhirs. Guernsey has two carved statue menhirs, while the dolmen known as L'Autel du Dehus contains a carved dolmen deity called Le Gardien du Tombeau.
Archaeological evidence indicates that Guernsey participated in regional trade during the Roman period. A third-century Gallo-Roman shipwreck was discovered in St Peter Port harbour. Excavations at Kings Road in St Peter Port uncovered silver from England, Breton pottery and wine amphorae, indicating maritime trade along the western coast of Europe.
Early history The arrival of Christianity
During their migration to Brittany, Britons settled in the Lenur islands, an early name for the Channel Islands. Historical sources variously identified Guernsey as Sarnia or Lisia, although later research has suggested that Sarnia may instead have referred to Sark. Sarnia nevertheless remains a traditional designation for Guernsey. Medieval records also used spellings including Gernesey, Gernesie and Gernezeye.
Tradition credits Saint Samson, who travelled from the Kingdom of Gwent and later became abbot of Dol in Brittany, with introducing Christianity to Guernsey.Marr, J., The History of Guernsey – the Bailiwick's story, Guernsey Press (2001).
A chapel, dedicated to Saint Magloire once stood in the Vale. Magloire, traditionally described as a nephew of Samson, was born around 535. A papal bull issued by Pope Adrian IV recorded the chapel as being under the patronage of Mont-Saint-Michel Abbey in Normandy, although no trace of the building survives. According to tradition, Magloire established a place of Christian worship in Guernsey before 600, but the chapel itself was probably built later.
In the late tenth century, Benedictine monks from Mont-Saint-Michel founded a priory dedicated to Saint Michael the Archangel at St Michel du Valle in northern Guernsey. Sources variously date its foundation to c. 962–968. The priory remained dependent on the abbey, and its former estates became known as the Fief Saint-Michel. Northern Guernsey was separated from the rest of the island at high tide until nineteenth-century land reclamation. The priory was distinct from the later Lihou Priory.
The Duchy of Normandy
In 933, Guernsey and the other Channel Islands came under the control of William Longsword, the son and successor of Rollo. The islands formed part of territories annexed from the Duchy of Brittany and incorporated into the Duchy of Normandy. Guernsey and the other Channel Islands are remnants of the medieval Duchy of Normandy and retain a constitutional relationship with the British Crown.
In 1020, Duke Richard II split Guernsey in half, between the viscounts of the Cotentin and the viscounts of Bessin. However, when one of the former's ancestor died heirless in around 1137, the fief reverted to the Duke, hence why it is named (the King's fief).
According to tradition, Robert I, Duke of Normandy (the father of William the Conqueror) was journeying to England in 1032, to help Edward the Confessor. He was obliged to take shelter in Guernsey and gave land, now known as the Clos du Valle, to the monks. Furthermore, in 1061, when pirates attacked and pillaged the Island, a complaint was made to Duke William. He sent over Sampson D'Anneville, who succeeded, with the aid of the monks, in driving the pirates out. For this service, Sampson D' Anneville and the monks were rewarded with a grant of half the Island between them. The portion that went to the monastery was known as Le Fief St Michel, and included the parishes of St Saviour, St Pierre du Bois, Ste. Marie du Catel, and the Vale. The part of Sampson was called fief of Anneville. Another version says that Sampson followed Duke William and fought Neel de Saint Saveur Nigel de Saint-Sauveur, who held the fief of de Bessin in Guernsey. The rebels were eventually defeated at the decisive Battle of Val-ès-Dunes (1047) and on this occasion Nèel, Viscount of Cotentin, fled to Brittany and forfeited his fief in Guernsey. This battle is described by Wace in his poem "Roman du Rou". In any case, in this version too, Sampson d'Anneville stands at the beginning of the actual feudal settlement of the island. Sampson built a manor house called Manor d'Anneville and had two sons. The founding of the Seigneurie and fief d'Anneville in one quarter of the island, followed by the settlement of various Norman lords, means that feudal settlement and organisation of the island had already taken place before the Conquest. This tradition, of course, underlines the special character of Guernsey. It is echoed by many historians. Other historians, such as James Marr, suggest that this second phase of development was longer and continued after the death of William in 1087 and the rise of Geoffrey of Anjou.
In 1066, the Duke William the Conqueror defeated Harold Godwinson at Hastings to become the King of England; however, he continued to rule his French possessions, including Guernsey, as a separate entity, as fealty was owed to the King of France. This initial association of Guernsey with England did not last long, as William split his possessions between his sons: Robert Curthose became Duke of Normandy and William Rufus gained the English Crown. William Rufus' brother Henry I recaptured Normandy for England in 1106. The island was then part of the English King's realm (though still part of Normandy and France). Around 1142, it is recorded that Guernsey was under the control of the Count of Anjou, who administered Normandy for the Duke.
Late Middle Ages The loss of Normandy by King John in 1204 isolated the Channel Islands from mainland Europe.
The loss of mainland Normandy by King John in 1204 was the defining event in Guernsey's constitutional history. The separation was not automatic: Norman seigneurs across the Duchy were compelled to choose their allegiance, and many sided with whichever power brought them the greatest advantage. Pierre de Préaux, Lord of the Islands since 1200, fought for King John against France but was defeated at Rouen; with his surrender on 24 June 1204, his lordship of the Channel Islands technically passed to France. For a brief period the islands belonged to neither the English Crown nor the conquered Duchy.
The subsequent decision of the island's seigneurs to confirm their allegiance to the English Crown—rather than follow the continental Duchy under France—was the foundational act of the islands' separate constitutional existence. King John responded by promising the islands the right to continue governing themselves according to their own laws and customs, privileges traditionally attributed to the so-called Constitutions of King John. The islands were never incorporated into the Kingdom of England through any Act of Union, but remained self-governing peculiars of the Crown.
In 1259, the Treaty of Paris formalised the arrangement: Henry III renounced his claim to the Duchy of Normandy while retaining the Channel Islands, which were confirmed as possessions of the Crown held separately from the Kingdom of England. The Bailiwick of Guernsey has since maintained an unwritten constitution deriving from this settlement, with the Sovereign holding the islands as successor to the Dukes of Normandy.
This constitutional separation also preserved the island's distinct legal identity. Over the following centuries, Guernsey defended its right to be governed by the Coutume de Normandie (the customary law of Normandy) rather than English common law, notably during the plaids of Quo warranto in the late 13th and early 14th centuries. The right to Norman customary law, the direct feudal relationship with the Crown, and the islands' self-governing institutions form the basis of Guernsey's continuing status as a Crown Dependency—self-governing but not part of the United Kingdom.
The feudal heritage rooted in the seigneurs' act of allegiance in 1204 continues to be maintained as a distinctive element of Guernsey's constitutional and cultural identity. In the absence of a written constitution, the continuing observance of Norman feudal customs serves as tangible evidence of the islands' separate status and their direct relationship with the Crown. The Court of Chief Pleas—the ancient court originally composed of the Bailiff, Jurats, and seigneurs holding fiefs directly from the Crown—continues to sit annually, with seigneurs of the fiefs nobles still required by the Court of Chief Pleas (Guernsey) Law, 2004 to perform Suit of Court (Secta Curiae). The ceremony of homage and reinvestiture, in which seigneurs reaffirm their vassalage to the Sovereign as Duke of Normandy — re-enacting the original act of allegiance that founded the islands' constitutional autonomy — remains the only feudal ceremony of its kind still practised in the world today.
Each time England and France went to war over the coming centuries, trade to and from the Channel Islands was restricted or banned and even when not officially at war, the island was repeatedly attacked by continental pirates and naval forces.
Fortifications were improved in the Channel Islands, manned by professional soldiers and the Guernsey militia who would help to defend the Island for the next 600 years. Service was compulsory in the militia for every man in the Island. Raids on Guernsey in 1336 and 1337 by exiled David Bruce, came at the start of the Hundred Years War, they were followed by Sark being captured and using this as a base, the next year when, starting in 1339, Guernsey was occupied by the Capetians, holding the Island for two years and Castle Cornet for seven. The attacks would recur on several occasions.
It was 1348 when the Black Death reached the Island, ravaging the population. In 1372, the island was invaded by Aragonese mercenaries under the command of Owain Lawgoch (remembered as Yvon de Galles), who was in the pay of the French king. Lawgoch and his dark-haired mercenaries were later absorbed into Guernsey legend as an invasion by fairies from across the sea.
In 1394 Richard II of England granted a new Charter to the islands. Because of great loyalty shown to the Crown, they were exempted for ever from English tolls, customs and duties.