Events that shaped english 

Anglo-saxons
In the fifth and sixth centruries the Anglo-Saxons and the jutes settled in England.
they spoke Germanic dialects. they settled in England and gave it its name - Engla Land which means land of the Angles and its language - Englisc.
Most of the Anglo - Saxons were farmers so Old english was full of words related to farming such as sheep, Shepard, ox, earth and field.
Its beacuse of the Anglo- Saxons that the modern English nation evolved.

Scandinavian settlement
Scaandinavian invanders came to Britain in the middle of the 9th century
They settled mainly in the northen and eastern areas. England had a Danish king in the 11th century.
Norse had a great influence on english. basic words such as take and they are borrowed from Norse.
The influence of Norse is not seen in written English until after the Norman Conquest.

The celts
The celts arrived 700 BC, they travelled from present-day France, established  trading centers which would later become important cities, yet apart from some place names, there are few Celtic words in today's English. The Celts were either assimilated or forced westwards, into what are today Wales, Scotland and Ireland. Their descendants still speak Celtic languages: Welsh, Scottish Gaelic and Irish Gaelic.

1066 and after
After William the Conqueor defeated Harold Godwinson at the battle of Hastings in 1066.
 English underwent enormous changes. Old English broke down and Middle English became quite similar to the English we see today.

Standardization
In the late medieval and early modern periods there was an ongoing process of standardizing English. There were many dialects in the Middle English period however, the London standard became dominant, particularly in the printed scripts.

Colonization and Globalization
Through British exploration and colonization, the English language spread throughout the world. It became a language of administration and diplomacy on every continent. English bacame a world language.