Louise Mack was born in Hobart, Tasmania to the family of a Wesleyan minister. Her younger sister Amy Eleanor Mack also became a writer. The family moved frequently for their father's work and settled in Sydney in 1882. She was educated by a governess and attended Sydney Girls High School. In 1896, she married John Percy Creed, an Irish-born lawyer. That same year, she published her first novel, The World is Round. Her only collection of poetry, Dreams in Flower, appeared in 1901. From 1898 until 1901, she wrote a column called "A Woman's Letter" for The Bulletin under the pen-name of "Gouli Gouli." She drew on her school memories for her books Teens (1897) and Girls Together (1898). In 1901, she moved to England, without her husband, and worked as a journalist on The Daily Mail. She published the novels An Australian Girl in London (1902) and Children of the Sun (1904). She lived in Florence for six years, editing the Italian Gazette. At the outbreak of World War I, she was in Belgium, where she went to work as the first woman war correspondent for the Evening News and the London Daily Mail. Her eyewitness accounts of the terrifying German invasion of Antwerp, the desperate flood of refugees fleeing the city, and other events were published as A Woman's Experiences in the Great War in 1915. Returning to Australia in 1916, she gave public lectures about her war experiences and wrote for The Sydney Morning Herald, the Bulletin, and other newspapers and magazines. In 1924, she married Allen Illingworth Leyland, 20 years her junior. Among her last novels were Teens Triumphant (1933) and Maiden's Prayer (1934).