His mother was Priscilla Ann Blake; his father was Matthew Dowdy Shiell, most probably the illegitimate child of an Irish Customs officer and a female slave.

His early literary reputation was based on two collections of short stories influenced by Poe published in the Keynote series by John Lane – Prince Zaleski (1895) and Shapes in the Fire (1896) – considered by some critics to be the most flamboyant works of the English decadent movement.

This began as a serial contracted by Peter Keary (1865–1915), of C. Arthur Pearson Ltd, to capitalise on public interest in a crisis in China (which became known as the Scramble for Concessions).

Around 1899–1900, Shiel conceived a loosely linked trilogy of novels which were described by David G. Hartwell in his introduction to the Gregg Press edition of The Purple Cloud as possibly the first future history series in science fiction.

Notebook II became The Lord of the Sea (1901), which was recognised by contemporary readers as a critique of private ownership of land based on the theories of Henry George.

[14] Shiel's lasting literary reputation is largely based on Notebook III of the series which was serialised in The Royal Magazine in abridged form before book publication that autumn as The Purple Cloud (1901).

The Purple Cloud is an important text of early British science fiction, a dystopian, post-apocalytic novel that tells the tale of Adam Jeffson, who, returning alone from an expedition to the North Pole, discovers that a worldwide catastrophe has left him as the last man alive.

[15] Demonstrative of the speculative, philosophical impulse that pervades Shiel's work, The Purple Cloud engages with Victorian developments in the sciences of geology and biology, tending to home in on their dark sides of geological cataclysm and racial decline in keeping with what has been termed the fin-de-siècle 'apocalyptic imaginary', while ultimately putting forward a positive if unorthodox view of catastrophe.

This novel was far from hackwork, and besides apparent autobiographical elements (including a minor character based on Ernest Dowson with whom Shiel is rumoured to have roomed briefly in the 1890s), contains some of his finest writing, but it was not reprinted in England, nor formally published in America.

The novel was a recasting of Romeo and Juliet into the ongoing war with leading families of the two nations standing in for the feuding Capulets and Montagues of Shakespeare's play.

"[22] Faced with declining sales of his books, Shiel tried to recapture the success of The Yellow Danger when China and Sun Yat-sen returned to the headlines during the Chinese Revolution of 1911–1912.

[24] Unrepentant, Shiel served sixteen months hard labour in prison, complaining to the Home Secretary about the law, though he assured his publisher Grant Richards in a letter that he had been treated well.

Shiel's discussion of his crime is disingenuous; he conceals from Richards the identity of his victim in addition to misleading him about her age, and instead refers to "love-toyings" with an older girl on the cusp of maturity.

However, as Macleod argues in her essay, young heroines abound in Shiel's novels, where they are romanticised, idealised and sexualised through the eyes of the male author.

Lazarus (also a 2,000-year-old immortal for the same reason) is warned ruefully against her: “If Rachel and you co-habit without some marriage-rite, you may see yourself in prison here in Europe, since it cannot be believed that she is as old as fourteen.”[27] Over the next decade Shiel wrote five plays, dabbled in radical politics and translated at least one, though probably more, pamphlets for the Workers Socialist Federation.

[29] Esther Lydia's first husband was William Arthur Jewson (July 12, 1856 - April 26, 1914), a prominent musician who had been born in London and died of a heart attack.

"[34] Excluding the collaborations with Tracy, Shiel published over 30 books, including 25 novels and various collections of short stories, essays and poems.

[35] It was credited as the loose inspiration for the film, The World, the Flesh and the Devil (1959), starring Harry Belafonte, Inger Stevens, and Mel Ferrer.

As of January 1, 2018, all of the works published during Shiel's lifetime have entered the public domain in the United Kingdom and all other countries with a copyright term of Life of the Author plus 70 years.