Jessie L. Weston, more precisely Jessie Laidlay Weston (1850-1928), was an English scholar who dedicated herself to studying medieval times, particularly Arthurian literature and folklore [Wikipedia].
While Weston dabbled in poetry early on, her most influential work is the book "From Ritual to Romance" (published in 1906). This book explored the Grail legend, proposing a radical interpretation that drew connections between ancient rituals and the literary development of the Grail stories [Princeton University Press].
Weston's work on the Grail legend proved highly influential. T.S. Eliot, the famous poet, credited "From Ritual to Romance" as a major source for his modernist poem "The Waste Land" [Goodreads]. Even today, Weston's book remains a valuable resource for those interested in Arthurian legends, mythology, and the history of religion.