William the Conqueror, the Duke of Normandy, invaded and conquered England in 1066. The Normans brought with them a form of Norman French which became the language of the nobility.
The lower classes continued to speak English. By the 14th century, English was once again the dominant language but featured many new words borrowed from French. Around 10,000 new words entered the language between the 11th and 15th centuries. These were mainly associated with government, religion, law, the military, clothing, food and alcohol.