The British government had passed the Tea Act seven months earlier on 10 May, partly in an attempt to support the struggling East India Company. The act allowed the company to import tea directly to the colonies, bypassing the middlemen who previously handled overseas tea sales and avoiding the issue of duty and refunds for importing tea into Britain. Tea imported into the colonies would consequently be much cheaper, and allow the East India Company to undercut the price of smuggled Dutch tea.
The problem for settlers in America was that tax was still imposed on tea in a continuation of the three pence duty that came in under the Townshead Acts of 1767. Although tea imported under the new Tea Act would still be cheaper than before, a number of colonists opposed the idea that the British government had the right to impose any tax at all on the colonies. Since they did not elect the British parliament they argued that the new Act violated their right to “no taxation without representation”.
The first shipment of tea to arrive in Boston under the new Act was brought by the Dartmouth in November. Colonialists gathered together by Samuel Adams urged the captain of the ship to sail back to Britain without paying the import duty, but Governor Hutchison refused to allow the ship to leave.
In the meantime two more ships arrived. Unable to resolve the standoff, on the evening of 16 December a group of up to 130 men, some disguised as Mohawk warriors, boarded the three vessels and threw all 342 chests of tea into the water. This act of defiance served as a catalyst for the American Revolution that broke out less than 18 months later.