The Gadsden flag is a historical American flag with a yellow field depicting a timber rattlesnake coiled and ready to strike. Beneath the rattlesnake are the words: "DONT TREAD ON ME". Some modern versions of the flag include an apostrophe.
The flag is named after politician Christopher Gadsden (1724–1805), who designed it in 1775 during the American Revolution. It was used by the Continental Marines as an early motto flag, along with the Moultrie flag. Its design proclaims an assertive warning of vigilance and willingness to act in defense against coercion.