The purpose of the Declaration of Independence was to list grievances against the British monarchy and summarize a philosophy of liberty held by the Continental Congress. The Declaration was written mainly by Thomas Jefferson, but it contained ideas expressed by many founding fathers as well as philosophers such as John Locke.
Over the course of several years prior to the 1776 signing of the Declaration, the Continental Congress cut ties to Britain through actions such as the Privateering Resolution, which said that colonists could outfit vessels with arms. In 1776, Richard Henry Lee made a resolution that the colonies absolve allegiance to the crown. Debate on the matter indicated the Lee Resolution would be adopted, so Congress convened a five-person committee to draft an independence statement; that statement became the Declaration of Independence.