- From Wikipedia: Sons of Liberty.
The Sons of Liberty was a loosely organized, clandestine, sometimes violent, political organization active in the Thirteen American Colonies founded to advance the rights of the colonists and to fight taxation by the British government. It played a major role in most colonies in battling the Stamp Act in 1765 and throughout the entire period of the American Revolution.
In popular thought, the Sons of Liberty was a formal underground organization with recognized members and leaders. More likely, the name was an underground term for any men resisting new Crown taxes and laws. The well-known label allowed organizers to make or create anonymous summons to a Liberty Tree, "Liberty Pole", or other public meeting-place. Furthermore, a unifying name helped to promote inter-Colonial efforts against Parliament and the Crown's actions. Their motto became "No taxation without representation."