When ships from England brought tea to the Americas the Sons of Liberty wanted them gone, but the governor of Massachusetts wanted it unloaded.
So on Dec 16, 1773 an organized protest group called The Sons of Liberty dressed up as Indians and dumped three hundred and forty two boxes of tea into the Boston harbor.
This was because of the import taxes on the tea. This made the colonist mad because the tea was the only thing being taxed and the colonist thought it would put local merchants out of business.
About one hundred men including Sam Adams boarded the ship (which they tried to send back to England) and dumped three hundred and forty two boxes of tea into the harbor.
The British were very angry with the colonist and took severe measures in what the colonist called the Intolerable Acts.
Maier, Pauline. "Boston Tea Party." World Book Online Reference Center. 2007. [Place of access. Date of access.] <http://www.worldbookonline.com/wb/Article?id=ar071320>.
Ritchie, Donald A., and Albert S. Broussard. American History The Early Years To 1877. Westerville,Ohio: Glencoe/McGraw-Hill, 1997.