Apprenticed in 1757 to William Bowyer the younger (known as “the learned printer”), who took him into partnership in 1766, Nichols undertook his first literary work as editor of the works of Jonathan Swift (1775–79). In 1778 Nichols became part manager of the Gentleman's Magazine and in 1792 sole managing editor. Of his original work, Bibliotheca Topographica Britannica (1780–90) and The History and Antiquities of the County of Leicester (1795–1815) are especially valuable. They are the fruit of his own meticulous observation and research. A friend of most of the leading literary figures of his age, he published Samuel Johnson's Lives of the English Poets, exercising much editorial influence and supplying a good deal of basic information. His own work as a biographer of the age began with his memoir of Bowyer, expanded into Biographical and Literary Anecdotes of William Bowyer (1782). This formed the basis of Literary Anecdotes of the Eighteenth Century, 9 vol. (1812–15; completed by his son, John Bowyer Nichols).