It all started with Julius Cesar, when he was the Romans Emperor. The Romans invaded Britain in 54-5, B.C. The 'Celtic' tribes lived in the British islands. Their Celtic languages still survive as the Gaelic in Scotland and Ireland, Welsh, in Wales, and Manx in the Isle of Man and Breton in France. The Romans brought Latin to Britain, which became part of the Roman Empire for over 400 years. Early English did not develop mainly from Latin. So it is different from French, Spanish and Italian, because they did not come directly from Latin. The Early English was the language of tribes who invaded from Germany, or the east in those times. They spoke different dialects of a 'Germanic' language, from which the modern German developed from. In 878 A.D, the Vikings took over Britain from Scandinavia, bringing with them the Norse language.
The appearance of the Norman army from France, defeated the English at the Battle of Hastings and brought very big changes to English life.
The Normans brought the Old French language, which became the language of the Royal Court, and the ruling and business class.
By the 1200.Kingdoms of England and France quit being united. The use of Old English came back but many french words were added. This language was called Middle English the language of a poet called Chaucer. He's said to be the greatest english poet before Shakespeare. It is said that his writings are hard to read by those who speak English.
The Renaissance in Europe, a time of great advance of learning and culture. In this time, English was not very different from the English used today. And the most famous person to write in English in this period was William Shakespeare.
Since Shakespeare the language has been changed...