He was a free African American almanac author, surveyor , naturalist and farmer . Born in Baltimore County, Maryland , to a free African American woman and a former slave , Banneker had little formal education and was largely self-taught. He is known for being part of a group led by Major Andrew Ellicott that surveyed the borders of the original District of Columbia , the federal capital district of the United States . Banneker's knowledge of astronomy helped him author a commercially successful series of almanacs. He corresponded with Thomas Jefferson , drafter of the United States Declaration of Independence , on the topics of slavery and racial equality . Abolitionists and advocates of racial equality promoted and praised his works. Although a fire on the day of Banneker's funeral destroyed many of his...