Eliza Haywood (née Elizabeth Fowler; c. 1693 – 25 February 1756), was an English writer, actress and publisher. An increase in interest and recognition of Haywood's literary works began in the 1980s. Described as "prolific even by the standards of a prolific age", Haywood wrote and published over 70 works in her lifetime, including fiction, drama, translations, poetry, conduct literature and periodicals. Haywood today is studied primarily as one of the 18th-century founders of the novel in English. She is especially famous for her novel Love in Excess (1719-20).

Scholars of Eliza Haywood universally agree upon only one thing: the exact date of her death. Haywood gave conflicting accounts of her own life; her origins remain unclear, and there are presently contending versions of her biography. For example, it was once mistakenly believed that she married the Rev. Valentine Haywood. According to report, Haywood took pains to keep her personal life private, asking the one (unnamed) person with knowledge of her private life to remain silent for fear that such facts may be misrepresented in print. Apparently, that person felt loyal enough to Haywood to honour her request.

The early life of Eliza Haywood is somewhat of a mystery to scholars. While Haywood was born "Elizabeth Fowler", the exact date of Haywood's birth is unknown due to the lack of surviving records. Although scholars believe that she was most likely born near Shropshire or London, England, in or around 1693, her birth date is extrapolated from a combination of her death date and her stated age at the time of her death (Haywood died on 25 February 1756 and obituaries notices list her age as sixty years).

Haywood's familial connections, education status, and social position are unknown. Some scholars have speculated that she is related to Sir Richard Fowler of Harnage Grange, who had a younger sister named Elizabeth. Others have stated that Haywood was most likely from London, England as several Elizabeths were born to Fowler families in 1693 in London; however, no evidence exists to positively confirm any of these possible connections. Her first entry in public records appears in Dublin, Ireland, in 1715. In this entry, she is listed as "Mrs. Haywood", performing in Thomas Shadwell's Shakespeare adaptation, Timon of Athens; or, The Man-Hater at the Smock Alley Theatre. Haywood described herself as a "widow", noting in 1719 that her marriage was "unfortunate", but no record of her marriage has been found and the identity of her husband remains unknown.

Scholars have speculated that Haywood had an affair and even a child with Richard Savage in the 1720s, in addition to a 20-year open relationship with William Hatchett, who was suspected of being the father of her second child. However, later critics have called these speculations into question as too heavily influenced by Alexander Pope's famous illustration of her in The Dunciad and too little based upon evidence. (Pope depicted Haywood as a grotesque figure with two "babes of love" at her waist, one by a poet and the other by a bookseller.) Other accounts from the period, however, suggest that her "friends" rejected Pope's scandalous depiction of her; they maintained that she had been deserted by her husband and left to raise their children alone. In fact, and despite the popular belief that she was once a woman of ill repute, Haywood seems to have had no particular scandals attached her name whatsoever.

Haywood's friendship with Richard Savage is thought to have begun around 1719. Savage wrote the gushing 'puff' for the anonymous Part I of her first novel, Love in Excess. The two appear to have been close in these early years, sharing many associates in literary and theatrical circles, even sharing the same publisher, William Chetwood. By September 1725, however, Savage and Haywood had fallen out, and he anonymously attacked her as a 'cast-off Dame' desperate for acclaim in The Authors of the Town. Savage is considered the likely impetus for Pope's attack on Haywood.

Haywood's association with Aaron Hill and the literary coterie known as The Hillarians seems to have followed a similar pattern as Haywood rose to fame. The Hillarians, a collection of writers and artists "committed to a progressive programme of ameliorating 'politeness'", included Savage, Hill, Martha Fowke, and for a time, Haywood. The group shared poems to and about each other, and formed a social circle of like minds. Haywood seems to have greatly admired Hill – who, though not a patron, seems to have promoted young, up-and-coming artists – and dedicated poems to him. She may have even seen him as a mentor during the earliest years of her career.

William Hatchett was a long-time colleague and collaborator. The two probably met around 1728 or 1729, and recent critics have touted the pair as domestic partners or lovers, though this suggestion has now been challenged. He was a player, playwright, pamphleteer and translator (and perhaps "sponge") who shared a stage career with Haywood, and they collaborated on an adaptation of The Tragedy of Tragedies by Henry Fielding (with whom she also collaborated) and an opera, The Opera of Operas; or, Tom Thumb the Great (1733). They also may have collaborated on a translation of Claude Prosper Jolyot de Crébillon's Le Sopha in 1742. Hatchett has even been seen as the father of Haywood's second child (based on Pope's reference to "a Bookseller" as a father of one of her children, though Hatchett was not a bookseller.) No clear evidence supporting this or a domestic partnership is extant.