Banneker’s most famous act of protest was his letter to Thomas Jefferson on August 19, 1791. Jefferson had written the Declaration of Independence, but he also enslaved over 100 people and had recently published Notes on the State of Virginia, where he speculated that Black people were inherently inferior to white people in both body and mind.
Knowing this, Banneker crafted a letter that was polite but razor-sharp. He didn’t just ask for freedom; he strategically dismantled Jefferson’s logic:
- Holding up a mirror to the Declaration: Banneker quoted Jefferson’s own words back to him, reminding him of the line: “We hold these truths to be self-evident, that all men are created equal.” He pointed out the staggering hypocrisy of holding such a “noble” view while simultaneously holding thousands of people in “groaning servitude.”
- Using the American Revolution as an analogy: Banneker cleverly compared the plight of enslaved Black people to the tyranny the American colonists felt under the British Crown. He reminded Jefferson how much the colonists valued their own liberty, asking how they could justify denying that exact same liberty to others.
- Providing physical evidence: Along with the letter, Banneker enclosed a handwritten copy of his upcoming astronomical almanac. He used his own calculations as living proof to refute Jefferson’s public claims about Black intellectual inferiority.

