Question: Olaf Stapledon and Maurice Maeterlinck, are British?

Context articles: Quadratic (collection)
Olaf Stapledon
Four Encounters
Death into Life
Maurice Maeterlinck
Star Maker
Monna Vanna
Georgette Leblanc
Nebula Maker
Last and First Men

Quadratic is a collection of four science fiction works by Olaf Stapledon and Murray Leinster.
 It was edited by William L. Crawford and published in 1953 by Fantasy Publishing Company, Inc. in an edition of 300 copies.
 The book is an omnibus of Stapledon's "Worlds of Wonder" and Leinster's "Murder Madness", created by combining unbound sheets from the publisher's previous editions of the two volumes.
William Olaf Stapledon (10 May 1886 – 6 September 1950) – known as Olaf Stapledon – was a British philosopher and author of science fiction.
 In 2014, he was inducted into the Science Fiction and Fantasy Hall of Fame.
Four Encounters is an unfinished work by the writer and philosopher Olaf Stapledon, written in the late 1940s but only published by Bran's Head Books in 1976, 26 years after the author's death.
 This edition contained an introduction by Brian Aldiss, a longtime champion of Stapledon's works.
 The text is also available in compilations of the author's writings.
Death into Life is a 1946 novel by Olaf Stapledon.
 Not strictly science fiction (the genre into which Stapledon's works are usually classified), the novel is described as "an imaginative treatment of the problem of survival after death".
 It deals primarily with the soul of a rear gunner who is killed in World War II, and who finds himself surviving his apparent death - first as part of a spirit bomber-crew, then as part of the spirits who were killed in the battle, and so on until finally his soul becomes part of a 'cosmical spirit'.
Maurice Polydore Marie Bernard Maeterlinck (also called "Comte (Count) Maeterlinck" from 1932; ] in Belgium, ] in France; 29 August 1862 – 6 May 1949) was a Belgian playwright, poet, and essayist who was Flemish but wrote in French.
 He was awarded the Nobel Prize in Literature in 1911 "in appreciation of his many-sided literary activities, and especially of his dramatic works, which are distinguished by a wealth of imagination and by a poetic fancy, which reveals, sometimes in the guise of a fairy tale, a deep inspiration, while in a mysterious way they appeal to the readers' own feelings and stimulate their imaginations".
 The main themes in his work are death and the meaning of life.
 His plays form an important part of the Symbolist movement.
 In later life, Maeterlinck committed plagiarism.
Star Maker is a science fiction novel by British writer Olaf Stapledon, published in 1937.
 The book describes a history of life in the universe, dwarfing in scale Stapledon's previous book, "Last and First Men" (1930), a history of the human species over two billion years.
 "Star Maker" tackles philosophical themes such as the essence of life, of birth, decay and death, and the relationship between creation and creator.
 A pervading theme is that of progressive unity within and between different civilizations.
 Some of the elements and themes briefly discussed prefigure later fiction concerning genetic engineering and alien life forms.
 Arthur C. Clarke considered "Star Maker" to be one of the finest works of science fiction ever written.
Monna Vanna (Russian: Монна Ванна ) is an unfinished opera by Sergei Rachmaninoff after a play by Maurice Maeterlinck.
 Rachmaninoff had completed Act I in short vocal score, with piano accompaniment, and then he went to ask for permission to set the text in a full three-act treatment.
 However, another composer, Henry Février, had by then received the rights to an operatic setting of the text.
 Had Rachmaninoff proceeded to a complete operatic setting, such a work could not have been produced in European countries that were signatories to copyright laws that covered the work of Maeterlinck.
 This opera could only have been produced in countries that at the time were not signatories to European copyright law, such as Russia.
 Ultimately, Rachmaninoff abandoned further work on this opera and never wrote a complete setting.
Georgette Leblanc (8 February 1869 Rouen, – 27 October 1941 Le Cannet, near Cannes) was a French operatic soprano, actress, author, and the sister of novelist Maurice Leblanc.
 She became particularly associated with the works of Jules Massenet and was an admired interpreter of the title role in Bizet's "Carmen".
 For many years Leblanc was the lover of Belgian playwright and writer Maurice Maeterlinck, and he wrote several parts for her within his stage plays.
 She portrayed the role of Ariane in "Ariane et Barbe-bleue", both in the original 1899 stage play by Maeterlinck and in the 1907 opera adaptation by Paul Dukas.
 Leblanc also appeared in a couple of French films, most notably "L'Inhumaine" in 1924.
 In the last few decades of her life she turned to writing, producing two commercially successful autobiographies and several children's books and travelogues.
Nebula Maker is a science fiction novel by Olaf Stapledon, published posthumously by Bran's Head Books in 1976.
 Probably written around 1932-33 (when Stapledon was working on "Odd John", his tale of a superhuman youth), the book is essentially a first draft of the author's 1937 opus "Star Maker", though there are many marked differences to the later, more polished work.
Last and First Men: A Story of the Near and Far Future is a "future history" science fiction novel written in 1930 by the British author Olaf Stapledon.
 A work of unprecedented scale in the genre, it describes the history of humanity from the present onwards across two billion years and eighteen distinct human species, of which our own is the first.
 Stapledon's conception of history is based on the Hegelian Dialectic, following a repetitive cycle with many varied civilisations rising from and descending back into savagery over millions of years, but it is also one of progress, as the later civilisations rise to far greater heights than the first.
 The book anticipates the science of genetic engineering, and is an early example of the fictional supermind; a consciousness composed of many telepathically-linked individuals.