Benjamin Banneker (November 9, 1731 – October 19, 1806) was a free African-American almanac author, surveyor, landowner and farmer who had knowledge of mathematics and natural history. Born in Baltimore County, Maryland, to a free African-American woman and a former slave, Banneker had little or no formal education and was largely self-taught. He became known for assisting Major Andrew Ellicott in a survey that established the original borders of the District of Columbia, the federal capital district of the United States.

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Banneker's knowledge of astronomy helped him author a commercially successful series of almanacs. He corresponded with Thomas Jefferson on the topics of slavery and racial equality, Jefferson having earlier drafted the United States Declaration of Independence. Abolitionists and advocates of racial equality promoted and praised Banneker's works.

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Although a fire on the day of Banneker's funeral destroyed many of his papers and belongings, one of his journals and several of his remaining artifacts are presently available for public viewing. Parks, schools, streets and other tributes commemorate him and his works. However, many accounts of his life exaggerate his accomplishments or attribute to him the achievements of others.

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From Wikipedia