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First of all, you are making a distinction that I don't quite like. You are directly implying that American English is not proper. I believe what you are trying to ask about is the difference between American English and RP English (Received Pronunciation). The main reason people believe that this RP English is the only proper English is because for many years it was the type of English spoken by the upper class British people, in fact it is sometimes also called Oxford English, Queen's English or BBC English.. However this is not a "type of English" It is simply an accent. In fact this accent hardly represents Britons because only about 2% of them speak it. It doesn't represent a geographical area, rather a social class. In general, we can't say something is more or less proper in English because we lack an Academy of the English Language. This type of institution does exist in many countries and their functions are to regulate what is accepted or not in each language. So in English the rule of thumb is, if people use it and accept it, it is English (largely influenced by dictionary publishers). As to who invented English, well the truth is that nobody "invents" a naturally developing language. Some constructed languages (which have been invented) such as Esperanto are known. To understand the origin of English, we must consider that the development of the language was a combined effort of many different civilizations. English began in what is now known as the UK, and it derives from many different cultures, the Anglos, the Jutes, the Saxons, the Celts... Many words were borrowed form other languages such as Latin, Greek and French (even when the English language already had practical words with the same meaning). English was taken to America when it was colonized, however according to Bill Bryson, the language has changed and developed slightly differently on each side of the ocean and in fact American English has more similarities to what was originally taken to the continent than the English spoken in the UK nowadays.