Louise Marley was born in Ross, California, in 1952, and grew up in both the Bay Area and in Montana. She currently resides and writes in the Pacific Northwest.

Marley's first book was Sing The Light (1995), which became the first of her Singers of Nevya trilogy ( Sing The Light, Sing The Warmth [1996], and Receive The Gift [1997]). A follow-up novel, Singer In The Snow, was released in 2005. The series tells the story of an ice planet where warmth and light necessary to survival are supplied by telepaths called Singers. The Singers use music to focus their powers and speed the path of warmth and light to the planet. The series is notable for its use as music as a major theme, something that runs through much of Marley (a professional music teacher as well as an experienced mezzo-soprano)'s work.

In 1999 Marley published The Terrorists of Irustan, the tale of a struggle for liberation by a group of women on a planet with a culture much like that of a patriarchal Middle Eastern Muslim society. The book was critically acclaimed and was nominated for the 2000 Endeavor Award, as well as a preliminary nomination for the 2001 Nebula for Best Novel. Marley followed up the novel with The Glass Harmonicain 2000. Glass Harmonica is a science fiction novel with aspects of historical fiction, with the title object (a real-life musical instrument invented by Benjamin Franklin) serving as a crosstime link between two female musicians, one of the 18th century and one of the 21st. The novel received the 2001 Endeavor Award.

Over the next few years, Marley wrote several additional science fiction novels, like her earlier ones using music and/or strong independent women as major components. The Maquisarde (2002) concerns a widow who strikes back against the oppression and lies of her society on a future Earth, while The Child Goddess (2004, winner of the 2005 Endeavor Award) tells the story of a female priest who struggles to protect a seemingly immortal child from a greedy corporation. Marley has also written three novels that combine fantastical elements with musical history: Mozart's Blood (2010), The Brahms Deception (2011), and The Glass Butterfly (2012).

Marley is a writer of short fiction as well, and has published a collection of short pieces, Absalom's Mother & Other Stories in 2007.  She has also written several novels under pseudonyms: As Toby Bishop she has written a series of novels under the rubric The Horsemistress Saga, about a group of winged horses and the psychically bonded women who learn to fly them (Airs Beneath The Moon [2007], Airs and Graces [2008], and Airs of Night and Sea[2009]). Under the name Cate Campbell, Marley is currently engaged on the Benedict Hall series, works of historical fiction about a rich 1920s Seattle family. Most notably, perhaps, as Louisa Morgan, Marley is writing a series about witches and their lives from historical through modern times. The first book in the series, A Secret History of Witches was published in 2017 and nominated for the 2018 Endeavour Award for Distinguished Novel/Collection. The second, The Witch's Kind came out in 2019 and the third, The Age of Witches, in 2020. The latest book in the series, The Great Witch of Brittany was released in 2022. Marley-as-Morgan will be releasing a ghost story novel, The Ghosts of Beatrice Bird*, in late 2023.