Born in Baltimore County, Maryland, to a free African-American mother and a father who had formerly been enslaved, Banneker had little or no formal education and was largely self-taught.

Banneker was born on November 9, 1731, in Baltimore County, Maryland, to Mary Banneky, a free black woman, and Robert, a freed slave from Guinea who died in 1759.

[6][9] According to that story, Molly purchased Banneka to help establish a farm located near the future site of Ellicott's Mills, Maryland, west of Baltimore.

The report noted that the name "Bannaker" may have had the same origin as that of Banaka, a small village in the present-day Klay District of Bomi County in northwestern Liberia that had once participated in the African slave trade.

[35][36][45] After returning to Ellicott's Mills, Banneker made astronomical calculations that predicted eclipses and planetary conjunctions for inclusion in an almanac and ephemeris for the year of 1792.

"[14] Rittenhouse responded to Pemberton by stating that Banneker's ephemeris "was a very extraordinary performance, considering the Colour of the Author" and that he "had no doubt that the Calculations are sufficiently accurate for the purposes of a common Almanac.

[14] Banneker's Pennsylvania, Delaware, Maryland and Virginia Almanack and Ephemeris, for the Year of our Lord, 1792 was the first in a six-year series of almanacs and ephemerides that printers agreed to publish and sell.

[30][53][54] The title pages of the Baltimore editions of Banneker's 1792, 1793 and 1794 almanacs and ephemerides stated that the publications contained: the Motions of the Sun and Moon, the True Places and Aspects of the Planets, the Rising and Setting of the Sun, Place and Age of the Moon, &c. – The Lunations, Conjunctions, Eclipses, Judgment of the Weather, Festivals, and other remarkable Days; Days for holding the Supreme and Circuit Courts of the United States, as also the useful Courts in Pennsylvania, Delaware, Maryland, and Virginia.

– Various Selections from the Commonplace–Book of the Kentucky Philosopher, an American Sage; with interesting and entertaining Essays, in Prose and Verse –the whole comprising a greater, more pleasing, and useful Variety than any Work of the Kind and Price in North America.

[55][56] In addition to the information that its title page described, the 1792 almanac contained a tide table listing the methods for calculating the time of high water at four locations along the Chesapeake Bay (Cape Charles and Point Lookout, Virginia; Annapolis and Baltimore, Maryland).

Written by a committee whose president was the city's mayor, Matthew Clarkson, the account related the presumed origins and causes of the epidemic, as well as the extent and duration of the event.

Having fully satisfied myself, in respect to his title to this type of authorship, if you can agree to him for the price of his work, I may venture to assure you it will do you credit, as Editors, while it will afford you the opportunity to encourage talents that have thus far surmounted the most discouraging circumstances and prejudices.

"[68] In their preface to Banneker's 1792 almanac, the editors of the work wrote that they:feel themselves gratified in the Opportunity of presenting to the Public, through the Medium of their Press, what must be considered as an extraordinary Effort of Genius — a complete and accurate EPHEMERIS for the Year 1792, calculated by a sable Descendant of Africa, .... — They flatter themselves that a philanthropic Public, in this enlightened Era, will be induced to give their Patronage and Support to this Work, not only on Account of its intrinsic Merit, (it having met the Approbation of several of the most distinguished Astronomers in America, particularly the celebrated Mr. Rittenhouse) but from similar Motives to those which induced the Editors to give this Calculation the Preference, the ardent desire of drawing modest Merit from Obscurity, and controverting the long-established illiberal Prejudice against the Blacks.

[74]The writer of a tribute in a 1796 Baltimore edition quoted a quatrain[76] and amended another[77] that an Englishman, Thomas Gray, had placed in a popular poem first published in 1751 (see Adaptations and parodies of Elegy Written in a Country Churchyard).

[78][79] The revised rhyme stated: Nor you ye proud, impute to these the blameIf Afric's sons to genius are unknown,For Banneker has prov'd they may acquire a name,As bright, as lasting, as your own.

[78][80]Supported by Andrew, George and Elias Ellicott and heavily promoted by the Maryland and Pennsylvania abolition societies, the early editions of the almanacs achieved commercial success.

The surviving journal described in April 1800 Banneker's recollections of the 1749, 1766 and 1783 emergences of Brood X of the seventeen-year periodical cicada (Magicicada septendecim and related species) and stated, "... they may be expected again in they year 1800 which is Seventeen Since their third appearance to me.

"[91] Describing an effect that the pathogenic fungus, Massospora cicadina, has on its host,[92] the journal further stated that the insects:.... begin to Sing or make a noise from first they come out of the Earth till they die.

[95] After quoting a statement that David Rittenhouse had made (that Negroes "have been doomed to endless slavery by us — merely because their bodies have been disposed to reflect or absorb the rays of light in a way different from ours"), the extract concluded:The time, it is hoped is not very remote, when those ill-fated people, dwelling in this land of freedom, shall commence a participation with the white inhabitants, in the blessings of liberty; and experience the kindly protection of government, for the essential rights of human nature.

Let the following sentence be inscribed in letters of gold over the door of every home in the United States: THE SON OF MAN CAME INTO THE WORLD, NOT TO DESTROY MEN'S LIVES, BUT TO SAVE THEM.

.... Sir, how pitiable is it to reflect, that altho you were so fully convinced of the benevolence of the Father of mankind, and of his equal and impartial distribution of those rights and privileges which he had conferred upon them, that you should at the same time counteract his mercies, in detaining by fraud and violence so numerous a part of my brethren under groaning captivity and cruel oppression, that you should at the Same time be found guilty of that most criminal act, which you professedly detested in others, with respect to your Selves.

no body wishes more 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, & that the appearance of a want of them is owing merely to the degraded condition of their existence both in Africa & America.

I have taken the liberty of sending your almanac to Monsieur de Condorcet, Secretary of the Academy of sciences at Paris, and member of the Philanthropic society because I considered it as a document to which your whole colour had a right for their justification against the doubts which have been entertained of them.

[28] When writing his letter, Banneker informed Jefferson that his 1791 work with Andrew Ellicott on the District boundary survey had affected his work on his 1792 ephemeris and almanac by stating: .... And altho I had almost declined to make my calculation for the ensuing year, in consequence of that time which I had allotted therefor being taking up at the Federal Territory by the request of Mr. Andrew Ellicott, ....[104][115]On the same day that he replied to Banneker (August 30, 1791), Jefferson sent a letter to the Marquis de Condorcet that contained the following paragraph relating to Banneker's race, abilities, almanac and work with Andrew Ellicott: I am happy to be able to inform you that we have now in the United States a negro, the son of a black man born in Africa, and of a black woman born in the United States, who is a very respectable mathematician.

I procured him to be employed under one of our chief directors in laying out the new federal city on the Patowmac, & in the intervals of his leisure, while on that work, he made an Almanac for the next year, which he sent me in his own hand writing, & which I inclose to you.

I shall be delighted to see these instances of moral eminence so multiplied as to prove that the want of talents observed in them is merely the effect of their degraded condition, and not proceeding from any difference in the structure of the parts on which intellect depends.

[127] An obituary concluded: Mr. Banneker is a prominent instance to prove that a descendant of Africa is susceptible of as great mental improvement and deep knowledge into the mysteries of nature as that of any other nation.

[137] The Library of Congress also holds a copy of Jefferson's August 30, 1791, handwritten letter to the Marquis de Condorcet that described Banneker's race, abilities, almanac and work with Andrew Ellicott.

[130][143] In 1996, a descendant of George Ellicott decided to sell at auction some of those items, including a drop-leaf table, candlesticks, candle molds, maps, letters and diaries.

[2] Several such urban legends describe Banneker's alleged activities in the Washington, D.C., area around the time that he assisted Andrew Ellicott in the federal district boundary survey.