[1][2] Wells originally pursued his initial line of inquiry into the types of possible life that might be found on Mars while developing a science fiction story in the mid-1890s that would later become the novel The War of the Worlds (1898).

[1] Lowell's claims convinced Wells of not just the habitability of Mars, but also for the idea that "it is inhabited by creatures of sufficient energy and engineering science to make canals beside which our greatest human achievements pale into insignificance.

", "Probable Appearance of the Martian Flora", "The Animal Kingdom", "No Fish on the Planet", "Climatic Conditions", "The Ruling Inhabitants", "How Like Terrestrial Humanity?

Unlike his previous work with writers, Leigh collaborated with Wells in coming up with the design of the Martian landscape, civilization, and creatures which could conceivably inhabit the planet.

[6] Historian Jennifer Tucker notes that Leigh's illustrations reflect a "sophisticated and innovative use of line and space, associated with new graphic design concepts in the early 1900s" with a "nod to modern symbols big and small", from the "iconography of world's fairs, monuments, and exhibitions to the fashionable dress and headband of the 'flapper' Martian girl".