Originally Posted by oyewaqar

I have found some points through internet, couldn't find much in any book. Could suggest a book in which this topic is covered?

Factors responsible
1. England's civil war (1642-1651)
Colonies lacked support of their mother country
2. Boundary Issues
Only two colonies had royal charters, while others were formed by dissenting groups.
3. Trade
Their economy depended on trade and fishing, and they had clashes on source and river routes.
4. Pequot War & Pan-Indian Confederation
Indian tribes had united against colonist
5. Rhode Island and Run away criminals
Criminals from one colony often escaped to others.
Rhode Island was not liked by other colonies because of their more liberal views and they wanted it to wither
6. Separation and self-government
Because of English Civil war they took it as an opportunity to separate themselves completely from England.

These are the points which I got from Internet, but the problem is that I don't think this will be enough for 20 marks question. My answer will span over 2-3 pages max.