The Revolutionary War started in 1775. The war started because the British were taxing the Colonists for there debts. The colonists didn't think that was right and they were trying to stand up for what was right.
On June 17, 1775, early in the Revolutionary War the British defeated the Americans at the Battle of Bunker Hill in Massachusetts. Inexperienced colonists caused many casualties to die during the battle.
The Declaration Of Independence was issued on July 4, 1776. The reason for creating this Letter was to try to resolve the issues between Colonies and have peace within them.