Wars have been fought over this. When I studied Spanish with other students all from different countries we were given the assignment to talk about the roots of our native languages. From other classmates I learned a about German, Japanese, French, Portuguese, etc. But for my part, I had no knowledge. A few searches via Google and after reading articles in wikipedia and other places http://www.englishclub.com/english-language-history.htm I learned a bit about the history of English. Basically English started in the days of the Saxons when the UK was settled by a bunch of tribes. Then in 1066, the Normans invaded England and for 400 years only the lower classes continued to speak English. The upper classes and official language were a form of French.

So blame the French!