English is a West Germanic language that originated from the Anglo-Frisian and Lower Saxon dialects brought to Britain by Germanic settlers and Roman auxiliary troops from various parts of what is now northwest Germany and the northern Netherlands in the 5th century. One of these Germanic tribes was the Angles, who may have come from Angeln, and Bede wrote that their whole nation came to Britain, leaving their former land empty. The names 'England' (from Engla land "Land of the Angles") and English (Old English Englisc) are derived from the name of this tribe.
The Anglo-Saxons began invading around 449 AD from the regions of Denmark and Jutland. Before the Anglo-Saxons arrived in England the native population spoke Brythonic, a Celtic language. Although the most significant changes in dialect occurred after the Norman invasion of 1066, the language retained its name and the pre-Norman invasion dialect is now known as Old English.
Initially, Old English was a diverse group of dialects, reflecting the varied origins of the Anglo-Saxon Kingdoms of Great Britain. One of these dialects, Late West Saxon, eventually came to dominate. One of the most prevalent forces in the evolution of the English language was the Roman Catholic Church. Beginning with the Rule of St Benedict in 530 and continuing until the Dissolution of the Monasteries in 1536, the Roman Catholic Church instructed monasteries and Catholic officials like Augustine of Canterbury to preserve intellectual culture within their schools, scriptoria, and libraries. During the Middle Ages, the Catholic Church had a monopoly on intellectual property in British society; in which they used to exert great influence on the English language. Catholic monks mainly wrote or copied text in Latin, the prevalent Medieval lingua franca of Europe. When monks occasionally wrote in the vernacular, it was common to substitute or derive English-like words from Latin to describe or refer to things in which there was no English word. Extensive vocabulary, a derivative of Latin vocabularium, in the English language is largely comprised from Latin word derivatives. It is believed that the intellectual elite in British society over the years perpetuated vocabulary that Catholic monks contributed to English; furthermore, they continued the custom of deriving new words from Latin long after the waning of Catholic Church. Old English vernacular was also influenced by two waves of invasion. The first was by language speakers of the North Germanic branch of the Germanic family; they conquered and colonised parts of the British Isles in the 8th and 9th centuries. The second was the Normans in the 11th century, who spoke Old Norman and developed an English variety of this called Anglo-Norman. (Over the centuries, this lost the specifically Norman element under the influence of Parisian French and, later, of English, eventually turning into a distinctive dialect of Anglo-French.) These two invasions caused English to become "mixed" to some degree (though it was never a truly mixed language in the strict linguistic sense of the word; mixed languages arise from the cohabitation of speakers of different languages, who develop a hybrid tongue for basic communication).
Cohabitation with the Scandinavians resulted in a lexical supplementation of the Anglo-Frisian core of English; the later Norman occupation led to the grafting onto that Germanic core of a more elaborate layer of words from the Romance languages. This Norman influence entered English largely through the courts and government. Thus, English developed into a "borrowing" language of great flexibility and a huge vocabulary.
With the emergence and spread of the British Empire, the English language was adopted in regions around the world, such as North America, India, Africa, and Australia. The emergence of the United States as a superpower has also helped the spread of English.
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