The underlying belief of the Declaration of Independence is that men have God-given natural rights and that government exists to protect those rights. The premise of this doctrine came from John Locke, who believed that if the government no longer serves to protect the needs of its citizens, then those citizens have the right to alter or abolish the government.
In the case of the 13 American colonies, there was growing dissatisfaction with British rule, culminating in a declaration of independence from rule by the king of England. The cornerstone of the Declaration of Independence, primarily written by Thomas Jefferson and adopted by the Continental Congress on July 4, 1776, is that all men are created equal. Based on that premise, there are inalienable rights, including the right to life, liberty and the pursuit of happiness. The new government is then obligated to lay a foundation on principles that are most likely to ensure safety and happiness as well as organize the government in a way that facilitates those goals. The Declaration of Independence firmly established that the colonies intended, among other things, to establish rule by representation, maintain a standing army and have trial by jury. The Declaration was signed by 56 delegates from the 13 colonies, including John Hancock, president of the Second Continental Congress.