Mary Webb was born in Leighton-under-the-Wrekin, Shropshire, England, on March 25, 1881 to George Edward and Sarah Alice Meredith. She was educated at home by her schoolmaster father, but spent two years in Southport attending a private school. Webb suffered from Graves's disease throughout her adult life, her most serious attack keeping her bedridden for several years at the age of twenty. She married Henry Webb in June 1912, and lived in Shropshire until 1921 when the couple moved to London. The Institut Français presented her with the Femina/Vie Heureuse prize for Precious Bane in 1926, acknowledging "the best imaginative work in prose or verse descriptive of English life by an author who has not gained sufficient recognition."

Her writings include the novels The Golden Arrow (London: Constable, 1916; New York: Dutton, 1935), Gone to Earth (London: Constable, 1917; New York: Dutton, 1917), The House in Dormer Forest (London: Hutchinson, 1920; New York: Doran, 1921), Seven for a Secret, A Love Story (London: Hutchinson, 1922; New York: Doran, 1923), Precious Bane (London: Cape, 1924; New York: Dutton, 1926), Armour Wherein He Trusted (London: Cape, 1929; New York: Dutton, 1929), a collection of essays entitled The Spring of Joy (London and Toronto: Dent/New York: Dutton, 1917; New York: Dutton, 1937), a poetry collection Fifty-one Poems Hitherto Unpublished in Book Form (London: Cape, 1946; New York: Dutton, 1947) and two anthologies Poems and the Spring of Joy (London: Cape, 1928; New York: Dutton, 1929) and Mary Webb: Collected Prose and Poems, edited by Gladys Mary Coles (Shropshire: Wildings, 1977).