The English language has been shaped by a number of other languages over the centuries, and many English speakers know that Latin and German were two of the most important. What many people don't realize is how much the French language has influenced English.
Without going into too much detail, I want to give a little bit of background about the other languages which shaped English. It was born out of the dialects of three German tribes (Angles, Jutes, and Saxons) who settled in Britain in about 450 A.D. This group of dialects forms what linguists refer to as Anglo-Saxon, and at some point this language developed into what we know as Old English. This Germanic base was influenced in varying degrees by Celtic, Latin, and Scandinavian (Old Norse) - the languages spoken by invading armies.