Although English is a Germanic language, approximately 30% of English vocabulary comes from French in one form or another. This is largely caused by an event called the Norman Conquest, in which a group of people called Normans, who inhabited Northern France and had a degree of Scandinavian ancestry, invaded and conquered England. The Old English-speaking aristocracy was mostly replaced by Norman French-speaking aristocracy, and for at least a hundred years, the nobility of England were primarily Norman French speakers. As a result, many words in English, particularly ones related to politics, warfare, and social class come from French. Many of these Norman French words are different from their modern French words, such as the word castle, from Norman French castel, in comparison to Modern French Château (which had evolved from Chasteau as indicated by the circumflex accent). Eventually, likely around the early or mid 13th century, the Norman/Angevin aristocracy of England lost most of their titles within the Kingdom of France and began to transition to English, which by this point was now full of French words. The higher nobility and Kings of England continued to speak French as their first language until sometime in the 14th or 15th century.

French words continued to enter the English language after England and France became more distinctly separate entities, as France and England were still geographic neighbors (there are quite a few Dutch and German words of French origin as well), and because for a long time French was the dominant language of European courts and was therefore a prestige language that many nobles of various countries learned. Frederick the Great of Prussia, for example, spoke French natively and may have preferred it to German, and the multi-ethnic and multi-lingual Austrian army often used French as a common language. Most of the English words and expressions that remain distinctly and obviously "French" come from these more recent vocabulary exchanges.