From Wikipedia

The Adventure Of English

Episode Five

The People's English

The establishment of the first permanent English-speaking colony in North America in 1607 was a major step towards the globalisation of the language. British English was only partially standardised when the American colonies were established. Isolated from each other by the Atlantic Ocean, the dialects in England and the colonies began evolving independently.

In the 19th century, the standardisation of British English was more settled than it had been in the previous century, and this relatively well-established English was brought to Africa, Asia and Oceania. It developed both as the language of English-speaking settlers from Britain and Ireland, and as the administrative language imposed on speakers of other languages in the various parts of the British Empire. The first form can be seen in New Zealand English, and the latter in Indian English. In Europe English received a more central role particularly since 1919, when the Treaty of Versailles was composed not only in French, the common language of diplomacy at the time, but also in English.