Patrick Henry had first got involved in the American Revolution because of the Parson's Cause case. This case was a dispute involving the Anglican clergy in a colony of Virginia. It was a big part leading up to the American Revolution.
In 1775, Henry presented his most famous speech, "Give me liberty or give me death." His speech made George Washington realize that people did not have much freedom to say what they think, and that had an important part in the American Revolution.
During Henry's speech he pointed out that the British government treated Americans poorly. He said this because people were not supposed to share their beliefs or they could be punished.
Henry finished off his speech by saying, "I know not what course others may take; but as for me, give me liberty or give me death!" His words stated that they need more American independence. That was a huge part leading up to the American Revolution.