Haynes became a martyr for the American cause after he was killed by British soldiers during the Boston Massacre.

Haynes made previously unknown contributions to the pamphlet Common Sense (1776).

Haynes served as an aide-de-camp to General George Washington and influenced the Continental Army’s strategy at the victorious battle of Yorktown.

Haynes responded to the Declaration of Independence in an essay that called for the abolition of slavery and establishment of civil rights for Black Americans.