She was the second wife of American art and literary critic William Crary Brownell (1851–1928); after his death she anthologized his work and wrote a memoir of their life together.

The New York Times compared Hall to Walter Pater and Théophile Gautier, and praised her "wonderful gift of language" and the "genuine power" of her storytelling.

"[13] Her last novel was Miss Ingalis (1918), set at "the end of the nineteenth century,"[14] about an idealistic young woman who finds herself at odds with the values of her wealthy fiancé's family.

[13]In 1919 Hall's novel The Truth about Camilla (1913) was adapted for the stage by Edith Ellis, as Bravo, Claudia, and opened in Pittsburgh with Mimi Aguglia in the title role, but the play was not a success.

In "The Three in Green" (subtitled "Märchen," a German word for fairy tale), a woodsman inadvertently fells three trees inhabited by female sprites.

"Garden Deadly" anticipates the sword and sorcery genre with the tale of a blighted kingdom, an enchantress who turns men into animals, and a brash, brawny hero who sets out to save the day.

In 1907 Hall published The Wagnerian Romances, based on the stories of Wagner's operas; the book "is not critique or commentary," she wrote in the introduction, "it is presentation, picture, narrative.

"This book of Miss Hall's is beautifully written, and the writer is a discerning critic who has spent her life among musicians of the first rank," who "has the rare gift of being able to reproduce the emotional effect of the Wagner operas upon the printed page; to suggest the setting, the scenic environment, the dramatic action, the personality of the characters.

At the age of seven she was taken to Florence, Italy, where for nine years she and her sisters were boarding pupils at a pensionnat de demoiselles that was later described in her 1913 novel The Truth About Camilla.

Only in the country summer did I grow used to what those to whom he mainly was a critic can hardly have suspected: his capacity for play—for entering unaffectedly into all sorts of foolish play, sharing pleasure in the littlest things that catch the wandering fancies of women.

She reflected on her husband's career, and wrote a memoir of their life together, in William Crary Brownell, an Anthology of His Writings Together with Biographical Notes and Impressions of the Later Years (1933).

[30] From at least 1938[30] Hall lived at 50 Central Park West, and resided there until a few weeks before her death, when a fall resulting in a fractured leg sent her to a nursing home.