English, the common language
The colonists of the Thirteen Colonies did not only come from England. There were people from Germany, the Netherlands, Sweden, Ireland, Scotland and the west coast of Africa. The Dutch living in New York and the Germans living in Pennsylvania retained their mother tongue for a few generations, but they would still assimilate into the English majority.
As for the black slaves, those in the North learned English, but the large landowners of the south wanted to limit their education. As a result, the southern slaves did not fully learn the English language; only the few words needed to communicate with their masters.
Over time, the English colonists continued to form the majority and dominated society, economy and politics. The English language had become the common language of the population.
Author: Léon Robichaud
See also – Traces of the past:
French (If available)