A primeira aparição da palavra "Sith" em ficção científica que eu encontrei é de Warlords of Mars por Edgar Rice Burroughs (1913-1914), que aparece em estas páginas .
Parece ser um inseto grande :
Sith: A giant, venomous hornet-like insect endemic to the Kaolian Forest.
Porges, Irwin; Burroughs, Hulbert; Bradbury, Ray (1975). Edgar Rice Burroughs: O homem que criou Tarzan (1ª ed.). Provo, Utah: Brigham Young University Press. p. 163. ISBN 978-0-8425-0079-1.
Burroughs pode ter derivado o nome do gaélico sith uma grafia alternativa de sidhe que significa fada.
A próxima aparição é de um robô chamado Sith Tal , um curador do museu robótico:
De Aventuras Incríveis, Volume 2, Monstros da Chama Viva (1951)
Em seu livro A história secreta de Star Wars , Michael Kaminski sugere que Lucas provavelmente recebeu a palavra "Sith" da série John Carter of Mars de Edgar Rice Burroughs. No Apêndice C do livro, Kaminski escreve:
Lucas took many of his inspiration for names from other languages of the world, mixing and matching sounds and vowels and inventing his own to create a uniquely alien language that also seemed bizarrely plausible. ... "Sith" is a word Edgar Rice Burroughs invented, as is "banths" ("banthas")
Algumas outras inspirações prováveis da Burroughs podem ser vistas em esta página (e também veja esta resposta que liga a um Entrevista do New York Times em que Lucas parece confirmar que a palavra "Jedi" foi inspirada na palavra "Jed" para os senhores marcianos em Burroughs). Kaminski observa que, ao escrever o Star Wars original, Lucas fez muitas pesquisas sobre trabalhos antigos de ficção científica e fantasia, incluindo o Burroughs, e cita as páginas 141-142 do livro de 1983 de Dale Pollock Skywalking: A vida e os filmes de George Lucas que diz:
Lucas returned from the local newsstand each weekend with a large collection of science-fiction magazines and comic books. Marcia wondered what was going on, but George told her not to worry, he was making a movie that ten-year-old boys would love...he thoroughly researched the science-fiction field from Buck Rogers and Flash Gordon to Stanley Kubrick's watershed film 2001: A Space Odyssey, made in 1968...Lucas also borrowed liberally from the Flash Gordon serials he had watched as a child, transplanting video screens, medieval costumes, art deco sets, and blaster guns to Star Wars...Lucas used Ming, the evil ruler of Mongo in the Flash Gordon books, as another model for his emperor. Alex Raymond's Iron Men of Mongo describes a five-foot-tall metal man of dusky copper who is trained to speak in polite phrases. From John Carter on Mars came banthas, beasts of burden in Star Wars; Lucas also incorperated into his early screenplay drafts huge flying birds described by Edgar Rice Burroughs. George watched scores of old films, from Forbidden Planet to The Day the World Ended, and read contemporary sci-fi novels like Dune by Frank Herbert and E.E. "Doc" Smith's Lensmen saga.
Como Richard observa em um comentário, a palavra "Sith" aparece em alguns roteiros iniciais do período em que estaríamos fazendo essa pesquisa, como este rascunho de 1974 (outros esboços e rascunhos incluindo a palavra são mencionados no livro de Kaminski também).
No capítulo 2, Kaminski também cita a primeira edição do boletim oficial de Star Wars , que novamente mostra Lucas se inspirando em Burroughs:
According to the first issue of Bantha Tracks, the official Star Wars fan club newsletter, Lucas also researched where Alex Raymond, the author and illustrator of the 1930s Flash Gordon comic strip, got his inspiration from, which led him to the John Carter of Mars novels by Edgar Rice Burroughs, which were similar in style and design.
e p. 16 de O Making of Star Wars oferece o que parece ser uma citação contemporânea de Lucas sobre Burroughs como uma influência:
"I've done a lot of reading for this picture. It's not really research so much as mythology and fantasy are taking over my life. I read everything from John Carter of Mars to The Golden Bough, so obviously all of that influences you in a certain way. I'm trying to make a classic genre picture, a classic space opera—and there are certain concepts that have been developed by writers, primarily Edgar Rice Burroughs, that are traditional, and you keep those traditional aspects about the project."