Benjamin Banneker was born in Baltimore County, the son of a freed slave. He was taught how to read and write by his grandmother and attended a Quaker school. He grew up working on his father's farm near the present town of Oella on the Baltimore County and Howard County border. When the Ellicott brothers arrived to build their mills in what is know Ellicott City, the Banneker's farm provided provisions. He and George Ellicott shared an interest in astronomy and became friends. George Ellicott loaned Banneker his telescope and books on astronomy.
Banneker's mechanical and scientific proficiencies were demonstrated when he became interested in the workings of a pocket watch. In 1753, at the age of 22, Banneker made a clock out of wood, carving each of the gears by hand and making all the necessary mathematical calculations. The clock he made worked for more than 40 years.
Banneker published almanacs between the years of 1792 and 1797. The almanacs contained charts that showed the phases of the moon and planets, and sunrises and sunsets. He also calculated the tides on the Chesapeake Bay. He did his own calculations which required him to be a keen astronomical observer and mathematician. Banneker sent a copy to Thomas Jefferson along with a letter urging him to take a stand against slavery. Jefferson replied that slavery was responsible for the degradation of blacks. Jefferson also wrote that he was sending Banneker's almanacs to the Secretary of the Academy of Sciences at Paris and members of the Philanthropic Society as proof of the capabilities of black people when not enslaved.
Major Andrew Ellicott asked Banneker to assist him in the survey of the nation's capital, Washington D.C. As Ellicott's assistant, Banneker was responsible for the care and operation of the astronomical equipment that was used to survey the 10-mile square area that became the District of Columbia.
Banneker died Oct. 25, 1806. The Federal Gazette, in its obituary, stated, "He was well known in the neighborhood for his quiet, peaceful demeanor, and among scientific men as an astronomer and mathematician.... Mr. Banneker is a prominent instance to prove that a descendant of Africa is susceptible of as great a mental improvement and deep knowledge into the mysteries of nature as that of any other nation."
The Banneker Historical Park and Museum is located in Oella across from Ellicott City.