Languages develop through contact with other languages - war, trade, conquest and shared knowledge lead to shared expressions and an intermingling of words. Guernsey's insignificance meant its linguistic fate tended to follow its ruling country, and its development is therefore closely related to that of French and English. This same insignificance, however, allowed Guernesiais to remain relatively undisturbed after the 16th Century.
Guernsey French is a surviving form of Norman, one of many local languages from ancient France. When Gaul was conquered by Rome in 55BC, Roman soldiers brought their language - a vulgar form of Latin which had developed through travel. Many Gauls adopted this new language to better communicate and trade with their occupiers, and this came to form a single language with elements of both. Combined with Frankish, this formed what is known as Langue d'Oïl, an umbrella term referring to a group of local languages in northern France derived from these sources. These were Burgundiy, Picardy, Wallon, Ile de France and - closest to the Channel Islands - Normandy.
The next significant influence on the language was Scandinavian. Tribes of "Nordmen" from the north invaded what was to become Normandy, and in 219AD the conquest was formalised when King Rollo of the Normans married the daughter of the King of France, Charles the Simple. The dowry was Normandy, where the Normans settled and adopted the local language. However, many Nordic elements also entered it at this point - including the words vraic, dehus and mielles. With the Norman invasion of England in 1066, this proto-French branched again into the Anglo-Norman spoken by the English rulers, and the Franco-Norman which survived in Normandy, and formed the basis of Guernsey French.
The language of both England and mainland Norman evolved further into modern French and English. After 1204, England lost Normandy to mainland France, and gradually Anglo-Saxon dominated its language once more, though it retained Norman influence. A different branch of the Langue d'Oïl was declared the official French language in 1515, rendering Norman archaic there also.
Guernsey, however, would not change hands again until 1945. Nor was there sufficient trade or travel to significantly influence the language. Instead, it remained a time capsule of Norman French.
This chapter is drawn from the following online resources: