Benjamin Banneker

Mathematician and astronomer Benjamin Banneker was born on November 9, 1731, in Ellicott’s Mills, Maryland. Largely self-taught, Banneker was one of the first African Americans to gain distinction in science. His significant accomplishments and correspondence with prominent political figures profoundly influenced how African Americans were viewed during the Federal period.

Portrait of Benjamin Banneker from the cover of his 1795 Almanac. Courtesy of the Maryland Historical Society

I apprehend you will embrace every opportunity, to eradicate that train of absurd and false ideas and opinions, which so generally prevails with respect to us [African Americans]; and that your sentiments are concurrent with mine, which are, that one universal Father hath given being to us all; and that he hath not only made us all of one flesh, but that he hath also, without partiality, afforded us all the same sensations and endowed us all with the same faculties…

Benjamin Banneker to Thomas Jefferson. August 19, 1791. Founders Online. National Archives

Banneker spent most of his life on his family’s 100-acre farm outside Baltimore. There, he taught himself astronomy by watching the stars and learned advanced mathematics from borrowed textbooks. In 1752, Banneker garnered public acclaim by building a clock entirely out of wood. The clock, believed to be the first built in America, kept precise time for decades.

In 1789, Banneker began making astronomical calculations that enabled him to successfully forecast a solar eclipse. His estimate, made well in advance of the celestial event, contradicted predictions of better-known mathematicians and astronomers.

Banneker’s mechanical and mathematical abilities impressed many, including Thomas Jefferson, who recommended him for the surveying team that laid out Washington, D.C. In his free time, Banneker began compiling his Pennsylvania, Delaware, Maryland, and Virginia Almanack and Ephemeris… The almanac included information on medicines and medical treatment and listed tides, astronomical information, and eclipses that Banneker had calculated. He published the journal annually from 1791 to 1802.

On August 19, 1791, Banneker sent a copy of his first almanac to then secretary of state Thomas Jefferson. In an accompanying letter, he questioned the slaveholder’s sincerity as a “friend to liberty.” Banneker urged the future president to fight for the abolition of slavery. Jefferson responded by expressing his ambivalence about slavery and endorsing Banneker’saccomplishments:

…no body [sic] wishes more sincerely than I do to see such proofs as you exhibit, that nature has given to our black brethren, talents equal to those of the other colours of men, and that the appearance of a want of them is owing merely to the degraded condition of their existence both in Africa & America…

Letter, Thomas Jefferson to Benjamin Banneker expressing his belief that blacks possess talents equal to those of “other colours of men,” 30 August 1791.(Thomas Jefferson Papers). Manuscript Division

Jefferson closed by informing Banneker that he had forwarded the almanac to the French philosopher the Marquis de Condorcet for the purpose of dispelling racial prejudices.

In other writings, notably Notes on the State of Virginia, Jefferson revealed conflicting perspectives on race. The notes in the record for Jefferson’s letter to Banneker include reference to correspondence with diplomat Joel Barlow and French clergyman Henri Gregoire in which Jefferson expresses less favorable attitudes toward African Americans.

Banneker died on October 25, 1806. His accomplishments continued to inspire African-Americans and provide ample evidence of African-American achievement in the sciences.

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