English, a West Germanic language in the Indo-European language family, has gone through three main periods in its history: Old English, Middle English and Modern English. Its roots are Germanic, but it has been heavily influenced by Latin and French, and it also has Old Norse influences.
English first came to the British Isles when three Germanic tribes conquered the land. When they mixed their dialects, Old English, also known as Anglo-Saxon, began. With the arrival of Christianity in 597 came new Latin words, mostly having to do with the church. Vikings invaded around A.D. 878, introducing words from Old Norse, another Germanic language. Examples of words with Old Norse origins include "window," "sky" and "egg."
Middle English came about after the Duke of Normandy conquered England and brought his Francophone nobles to form the new government. English was now the language of the lower class. About 150 years later, the French left but many French words remained in the language. Many of these words had to do with power, such as "crown," "castle" and "army."
Modern English came about around 1500 with England's first printing press, which standardized English. Many new Latin and Greek words entered the English language during the Renaissance, due to an increase of interest in the arts and travel. The Industrial Revolution also brought new words to the language, as new words had to be invented to keep up with technology. New words also entered the language via British colonialism. For example, the word "kangaroo" comes from Australian Aboriginals.