In 1928, she moved to England and found herself in the heart of London's thriving literary scene.
Inspired by the rise of emerging female authors such as Christie, Dorothy Sayers and Margery Allingham, Marsh decided to try her hand at crime writing, penning her debut novel, A Man Lay Dead, in 1931.
But before she could meet with publishers, she was called back to New Zealand after the sudden death of her mother. Instead, she posted her manuscript before she boarded the ship home. Weeks later, she received a letter from London accepting the murder mystery for publication.
Marsh's success was rapid and far-reaching. She quickly became one of publishing's best-selling authors, becoming even more popular than Christie. In 1949, her publishers released a million copies of Marsh's books, all of which sold.
Much of her success was thanks to her main character, Chief Inspector Roderick Alleyn, who went on to feature in all 32 of her detective novels. Marsh was also unique in setting some of her novels in New Zealand.
Biographer Joanne Drayton says Marsh's success was more impressive as she achieved it from New Zealand, at a time when it was still a distant outpost of the British Empire.
"In terms of distance and communication, it was a long, long way from anywhere. But she made New Zealand central," Drayton explains.
In addition to writing novels, Marsh was also an accomplished poet, painter and successful theatre director.
Famously independent, Marsh never married or had children, which some believe explains why her legacy faded more quickly than the likes of Christie.
As author Stella Duffy explains: "Christie's estate is very much pushed by her grandson in Britain. That's why her books have remained in the public eye."
When Marsh died in 1982, her death made headlines around the world. An obituary published in the New York Times quoted critic Newgate Callender as saying: "She writes better than Agatha Christie ever did: She is more civilised, knows something of the arts, and her characterisations have much more life than Christie's cardboard figures ever did."
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