What event prompted the formation of the 1st continental Congress

The event that prompted the formation of the First Continental Congress was the Boston Tea Party.

It refers to the even where Americans were sick of taxation that the British government imposed on them, so they decided to take matters into their own hands. In 1773, a group of angry Americans threw 342 chests of tea into the water as a form of defiance. After that, the First Continental Congress was called where twelve American Colonies met to decide what to do next.