Colonists in Boston, unhappy with the Tea Act passed by the British Parliament, boarded ships in Boston Harbor and threw their cargo of tea overboard in an act of protest known as the Boston Tea Party. This event occurred on December 16, 1773 in Boston Harbor in response to the Tea Act that had been passed, which colonists saw as a overreach of power by the British. The Boston Tea Party was a key event leading up to the American Revolutionary War.