While Jeter's Morlock Night and Infernal Devices, Powers' The Anubis Gates, and Blaylock's Lord Kelvin's Machine were the first novels to which Jeter's neologism would be applied, they gave the term little thought at the time. However, they were far from the first modern science fiction writers to speculate on the development of steam-based technology or alternate histories. Keith Laumer's Worlds of the Imperium (1962) and Ronald W. Clark's Queen Victoria's Bomb (1967) apply modern speculation to past-age technology and society. Michael Moorcock's Warlord of the Air (1971) is another early example. Harry Harrison's novel A Transatlantic Tunnel, Hurrah! (1973) portrays a British Empire of an alternative year 1973, full of atomic locomotives, coal-powered flying boats, ornate submarines, and Victorian dialogue. In February 1980 Richard A. Lupoff and Steve Stiles published the first "chapter" of their 10-part comic strip The Adventures of Professor Thintwhistle and His Incredible Aether Flyer.
The first use of the word in a title was in Paul Di Filippo's 1995 Steampunk Trilogy,[15] consisting of three short novels: "Victoria", "Hottentots", and "Walt and Emily", which, respectively, imagine the replacement of Queen Victoria by a human/newt clone, an invasion of Massachusetts by Lovecraftian monsters, and a love affair between Walt Whitman and Emily Dickinson.
Source: wikipedia.org