My answer might not be as good as the first answer but I'll try to give you a simple answer to your question. Yes, language is highly a cultural product in which people (through communicating with eachother, with other people from other places) add new concepts. English language was basically a mixture between two major forces which are (Germanic: Dutch, German, [im not sure if there are others]. These are the main components of Old English. If you read old texts you'll notice that most of the vocabulary taken from German, becuase back then England was conqured by the Anglo-Saxons. But after the Norman conquest 1066 (French), new terms and words intered the language. These mostly came from Latin. (Romance languages: Italian, French, Spanish).
This is basically the two main incedents that shaped the English langauge. Of course you should mention the cultural products (the major events that took place later on) such as: the Renaissance, Industrial Revolution whichh really have a great impact on the western culture, inventions ( movable-type printing press, TV...etc)
The present English language is a hodgepodge .For , in course of its development from Celtic language ,-the original language of the forefathers of the English , it shared the Raman language , German languge , Scandinavian language , and the French language .
There was Roman occupation from 43 A.D to 410 .The Celts served the Romans .Then , after the withdrawal of Roman troops , the Celts were often raided by the Picts and Scots .The Celtic people to have their seafty invited the Jute ,-a ferocious Germanic tribe .Then the Jute invited the other two Germanic races ,-Saxon and Angle .It continued from the middle of the 5th century to the opening of the 6th century .After this the major change occured from 1066 , with the Norman Conquest .
So , the Celtic language , through Roman , German , and French language , lost its originality , and a hybrid of German and French , came up as the present English language .