Why were the colonies established in the first place?

They were established because many of the people who came over were refugees and facing religious prosecution in Europe so they decided to live on the unknown northern part of the Americas. The first colonies in North America were along the eastern coast. Settlers from Spain, France, Sweden, Holland, and England claimed land beginning in the 17th century. The struggle for control of this land would continue for more than a hundred years.
The first permanent settlement in North America was the English colony at Jamestown, in 1607, in what is now Virginia. John Smith and company had come to stay. The Pilgrims followed, in 1620, and set up a colony at Plymouth, in what is now Massachusetts.
Other English colonies sprang up all along the Atlantic coast, from Maine in the north to Georgia in the south. Swedish and Dutch colonies took shape in and around what is now New York.
As more and more people arrived in the New World, more and more disputes arose over territory. Many wars were fought in the 1600s and 1700s. Soon, the two countries with the largest presence were England and France.
The two nations fought for control of North America in what Americans call the French and Indian War (1754-1763). England won the war and got control of Canada, as well as keeping control of all the English colonies.
By this time, the English colonies numbered 13. They were Massachusetts, New Hampshire, Connecticut, Rhode Island, New York, New Jersey, Pennsylvania, Maryland, Delaware, Virginia, North Carolina, South Carolina, and Georgia.