From the appearance of her first novel A Romance of Two Worlds in 1886, she became a bestselling fiction-writer, her works were largely concerned with Christianity, reincarnation, astral projection and mysticism.

She was associated at some point with the Fraternitas Rosae Crucis; a Rosicrucian and mystical organization,[11][12][13] and her books were a part of the foundation of today's corpus of esoteric philosophy.

In 1902 she wrote to the editor of The Gentlewoman to complain that her name had been left out of a list of the guests in the Royal Enclosure at the Braemar Highland Gathering, saying she suspected this had been done intentionally.

The editor replied that her name had indeed been left out intentionally, because of her own stated contempt for the press and for the snobbery of those wishing to appear in "news puffs" of society events.

There she fought hard for the preservation of Stratford's 17th-century buildings, and donated money to help their owners remove the plaster or brickwork that often covered their original timber-framed façades.

[17] Novelist Barbara Comyns Carr mentions Corelli's guest appearance at an exhibition of Anglo-Saxon items found at Bidford-on-Avon in 1923.

She did not identify herself as a lesbian, but several biographers and critics have noted the frequent erotic descriptions of female beauty that appear in her novels, although they are expressed by men.

Her love for the long-married painter, her only known romantic attachment to a man, remained unrequited; in fact Severn often belittled Corelli's success.

She finally allowed a photograph of herself to be published as the frontispiece of her 1906 novel Treasure of Heaven, though it was apparently airbrushed to depict her as "a sweet young lady in her early twenties".

[32] Around the same time, Mark Twain wrote the following description of Corelli's appearance in his diary during a visit to Stratford: She is about fifty years old but has no grey hairs; she is fat and shapeless; she has a gross animal face; she dresses for sixteen, and awkwardly and unsuccessfully and pathetically imitates the innocent graces and witcheries of that dearest and sweetest of all ages...[33]Corelli is generally accepted to have been the inspiration for at least two of E. F. Benson's characters in his Lucia series of six novels and a short story.

[35] In Chapter III of Bruce Marshall's The World, the Flesh and Father Smith, the protagonist – a Catholic priest – is in hospital, recovering from a wound.

It was directed by François Ozon, who stated, "The character of Angel was inspired by Marie Corelli, a contemporary of Oscar Wilde and Queen Victoria's favourite writer.