Benjamin Banneker was born in Endicott, Maryland on November 9, 1731. His mother was a free black woman and his father was a slave owned by his mother. 

Benjamin attended a public school run by the Quakers as a free Black and showed an early propensity for mathematics.  At the age of twenty-one, after viewing and then dismantling a friends watch, he built a wooden clock that kept accurate time for over forty years.

In 1790, Thomas Jefferson appointed Banneker as a member of the surveying team that was to lay out the plans for Washington, DC. The original chief architect of the project, Pierre L'Enfant was fired and took the plans with him when he left. Banneker was then placed in charge. He recreated the plans from memory and completed the project. 

In 1971 he published an Almanac concerning his observations on astronomy.  Banneker mailed a copy of this almanac to Thomas Jefferson along with a letter as a counter to Jefferson's belief in the inherent intellectual inferiority of the Negro. Jefferson  apologized and sent a favorable reply in a return letter. Jefferson also forwarded a copy of the Almanac to The French Academy of Sciences. Benjamin continued to publish his Almanac until 1802. He died on October 9, 1806.

ADDITIONAL MATERIAL:

Benjamin Banneker: Mathematician, Astronomer

Letter, Thomas Jefferson to Benjamin Banneker