Born in London, at age 12 his impoverished parents sent him to Virginia to work as a scribe for a mercantile firm. As an indentured servant he was of low social status; as a literate and ambitious young man he used politics to move upward in society. He graduated the College of William and Mary and was one of the early members of Phi Beta Kappa. By 1783 he had amassed 49,000 acres of rich, unoccupied land in the west, but it was tied up in litigation.

James Madison sponsored him as Clerk of the House in 1789. He associated with the radicals (especially fellow immigrants) and became an enthusiastic supporter of the French Revolution. He wrote frequently for Philip Freneau's National Gazette and Benjamin Bache's General Advertiser becoming known as an articulate exponent of American republicanism. He used the press energetically to denounce Hamilton and the Federatlists as crypto-monarchists whose corruption was subversive of American values. By 1792 he was starting a propaganda machine for the new Republican party that Jefferson and Madison were forming. Thus he told Madison in May 1795, "I enclose eight copies of the 'Political Observations.' I brought two dozen from New York and have distributed them all. I expect 50 more in a day or two, and shall scatter them also - they were bought and dispersed in great numbers there, and are eagerly enquired after by numbers here - it will be republished in Boston, Portsmouth, Vermont, and at Richmond." In 1795 he took the lead in denouncing Jay's Treaty, and had emerged as the most visible spokesman of the new Republican Party. Writing under the sobriquet of "A Calm Observer," in 1796 he charged that, among other heinous offenses, George Washington had stolen public funds and that he richly deserved impeachment.

In 1796 he managed the Jefferson campaign in Pennsylvania, blanketing the state with agents who passed out 30,000 hand-written tickets, naming all 15 electors (printed tickets were not allowed). Thus he told one agent, "In a few days a select republican friend from the City will call upon you with a parcel of tickets to be distributed in your County. Any assistance and advice you can furnish him with, as to suitable districts & characters, will I am sure be rendered. He is one of two republican friends, who have undertaken to ride thro' all the middle & lower counties on this business, and bring with them 6 or 8 thousand tickets." Beckleycampaign thus becFederalistsame the first American professional campaign manager. Federalists had him removed as House clerk in 1797. His allies in Pennsylvania soon found him a state job and he became even more active in promoting the Jefferson candidacy in 1800. Jefferson rewarded him with his old post of Clerk of the United States House of Representatives; Beckley got the House to add on the title of Librarian of Congress.

His son Alfred Beckley founded the town of Beckley on the western lands and named it in honor of his father.