The British government had not regarded the thirteen colonies, with their different social structures and political systems, as essential parts of the empire as a whole. ‘The Revolution's origins’ explains that when the French threatened to take control of the continent's interior, the colonists did not unite in the interest of the British Empire. American opponents of the Stamp Act, which Parliament passed in 1765, called themselves Sons of Liberty. This group turned resistance into full-scale revolt. The 1767 Townshend Acts, new revenue laws taxing imports into the colonies, ignited renewed political and social agitation, including a boycott of British goods.