William Henry Fox Talbot, pioneer of photography, was born on 11 February 1800 at Melbury, Dorset, the only child of William Davenport Talbot (1764–1800), army officer, of Lacock Abbey, Wiltshire, and Elisabeth Theresa (1773–1846). His father died when his son was five months old, and Talbot and his mother moved to a succession of family homes. In 1804, Lady Elisabeth married Captain (later Rear-Admiral) Charles Feilding (1780–1837). Talbot gained two half-sisters, Caroline Augusta Feilding (1808–1881; later Lady Mount Edgcumbe) and Henrietta Horatia Maria Feilding (1810–1851; later Horatia Gaisford).

Following initial tutoring at home and in Sussex, Talbot was accepted at Harrow School in 1811. He entered Trinity College, Cambridge, in 1817, becoming a scholar in 1819. On 20 December 1832 Talbot married Constance Mundy (1811–1880) of Markeaton in Derbyshire. Almost simultaneously, he was elected to parliament as the reform candidate for Chippenham.

Talbot met John Herschel in Munich in 1824, having already published six papers in mathematics. This chance meeting established a friendship and a scientific collaboration crucial to Talbot's later success. In 1826 Herschel introduced him to the Scottish natural philosopher David Brewster; Brewster's and Talbot's researches on light frequently overlapped, Brewster began publishing Talbot's scientific articles in his journal. In 1831 Talbot was elected a fellow of the Royal Society.

In October 1833, on the Italian shores of Lake Como, Talbot found himself unable to sketch the scenery, and began to conceive of a way to fix image onto paper. Thus was the concept of photography born. Talbot possessed no facilities for experimenting while travelling and was immediately plunged back into parliamentary duties on his return to England. At Lacock Abbey, some time later in spring 1834, he began to turn his dream into reality. By coating ordinary writing paper with alternate washes of table salt and silver nitrate, he embedded a light-sensitive silver chloride in the fibres of the paper. Placed in the sun under an opaque object such as a leaf, the paper would darken where not defended from light, producing a photographic silhouette. He called the resulting negatives ‘sciagraphs’—drawings of shadows.

He continued his researches in Geneva during the autumn. Unable at this stage to use his paper in the camera, he asked an unidentified artist friend to scratch a landscape design into opaque varnish coated on glass. Using this as a negative, he then made multiple copies on his photographic paper, originating the artistic technique later known as cliché-verre. It was also in Geneva that Talbot first mentioned stabilizing his images against the further action of light by washing them with potassium iodide—a process now called fixing.

In the summer of 1835, Talbot laboured to increase the sensitivity of his coatings sufficiently to make camera negatives practical. He realized that his negatives could themselves be printed on sensitive paper, reversing the tones back to normal, and allowing the production of multiple prints from one negative. While his cameras at this stage were small, crude, wooden boxes, left about the grounds of Lacock Abbey for long exposures, the fundamental concepts of permanent negative–positive photography were all within Talbot's grasp two years after his initial frustration at Lake Como.

In 1836, because of his investigations of crystals, he was invited to give the Bakerian lecture to the Royal Society. In 1838 he received the society's royal medal for his work in mathematics. By the start of 1839 he had published nearly thirty scientific papers and two books, with two more to follow within the year.

During November 1838 Talbot finally returned to his photographic experiments and started drawing up a paper for presentation to the Royal Society. Word came from Paris in January 1839 that Louis Jacques Mandé Daguerre had frozen the images of the camera obscura. On 25 January 1839, Michael Faraday displayed some of Talbot's still-preserved 1835 examples at the Royal Institution. On 31 January, Talbot's ‘Some account of the art of photogenic drawing’ was read before the Royal Society. This hastily written but wide-ranging paper gave a new name to his process and explored many of its implications. Three weeks later, he detailed his working procedures before the Royal Society.

Daguerre's method, disclosed seven months later, proved to be totally different from Talbot's, but the damage was already done. Fervent support by the French government and impressive early results gave the Frenchman an early lead. The Royal Society gave him little support, refusing to publish his work on photography in its Transactions.

In June 1844 Talbot began selling his serial The Pencil of Nature, illustrated with original photographic prints and designed to demonstrate the potential of photographic publication. In 1845 he issued by subscription Sun Pictures in Scotland, illustrated with twenty-three original photographic prints. Another 6000 original prints were supplied to the Art-Union for inclusion in its 1846 volume. However, this all went wrong; when put to the test of mass production the difficulties of photographic publishing were brought to the fore. Each hand-coated sheet of paper was exposed under fickle sunlight, then fixed and washed, often with inadequate or contaminated water supplies. The Pencil of Nature, a bold effort ahead of its time that had drawn praise from contemporary critics, was discontinued after twenty-four prints in six fascicles had been issued.

Other complications ensued. Of Talbot's various patents, four were for motive power, two dealt with metallurgy, and six were concerned with aspects of photography. None of his patents was lucrative and the ones for photography began to cause him great anxiety. His motivations for patenting photography were complex, but arose in part from the tense competitive circumstances of 1839. Whereas Daguerre received lavish French government support and public recognition, Talbot was all but ignored by his own government. He had freely published photogenic drawing, but received little recognition. While the terms he set for the calotype patent were generous, it undoubtedly limited the spread of photography on paper in the 1840s, at a time when resentment against patents in general was widespread.

Scott Archer's 1851 wet collodion process produced a glass negative by bringing out a latent image in a chemical developer, but Talbot felt that its conceptual basis lay in his original invention, and should be covered by his patent. Meanwhile, wealthy amateurs, interested in forming a photographic society, viewed Talbot's patent as an impediment. He was persuaded by 1852 to relinquish all coverage save for the commercial production of portraits. Even Talbot's priority of invention was contested, with implications that he had appropriated others' work. When tested in court in December 1854, in spite of affidavits by Sir John Herschel and Sir David Brewster, Talbot's patent was disallowed. The court recognised him as the true inventor of photography but ruled that newer processes were outside his patent.

This ruling came as a great personal blow to Talbot, adding to the chronic ill health that dogged him in the closing years of the 1840s. Removed from further experimenting, he ceased to take original photographs. However, as his health began to recover in the 1850s, Talbot proved far from discouraged, as he began building on experiments dating from the very beginnings of his photographic researches. Finally accepting that silver images could never be made truly permanent, he sought a way to realize his photographic images in time-proven printers' methods. In 1852 he patented his ‘photographic engraving’ process, which produced an intaglio plate that could be printed by conventional methods—the final rendering of the photographic image was in stable printer's ink. Spending more time resident in Edinburgh, he was able to draw on its innovative printing industry. By 1858 he had evolved a much improved process which he called ‘photoglyphic engraving’ and a second patent was granted. The 1862 International Exhibition in London awarded him a prize medal for photoglyphic engraving.

Talbot remained intellectually active throughout his life. In later years, in addition to his work on photoglyphic engraving, he turned increasingly to studies of the Assyrian cuneiform, publishing many important translations. After many years of heart disease he died in his study at Lacock Abbey on 17 September 1877; he was buried at Lacock.