when did the word "Alien" begin referring to extraterrestrial beings?

The etymology of the word "alien" goes as follows:

c.1300 (…)from Latin alienus "of or belonging to another, not one’s own, foreign, strange,"

first as an adjective and later transferred to a noun,

"foreigner, citizen of a foreign land," early 14c., (…) In the science fiction sense "being from another planet," from 1953.

according to this article:

the term arose sometime in the mid-14th century and was initially used to describe something as strange or of foreign origin. When dark age monks described something as alien, they meant it seemed unnatural within the context of the society and ecosystem.

and according to the same article:

The first recorded use of alien to mean “not of the Earth” was in 1920 — though one suspects it had happened previously. The word took off with the invention of the aircraft and the subsequent invention of the space shuttle.

And the OED puts some early examples:

1929 J Williamson in Sci. Wonder Stories July 102 (title) The alien intelligence.
/ 1932 C.A. Smith in Wonder Stories Aug. 224/1 The alien ship was now hanging near the tops of the giant plants

I think it is safe to assume the word’s connotation with the unworldly, did not begin to overthrow the worldly/of this earth definition until the 1950s when the great science fiction pictures began to be released like, Forbidden Planet, The Thing From Another World, etc. and those delightfully gruesome Mars Attacks cards from Topps.
Prior to the word "alien" I assume extraterrestrial beings, like those that appear in H.G. Wells’s War of the Worlds, were more likely referred to simply as Martians which is from 1877 in reference to "an inhabitant of mars", and similarly, Neptunian (1870), Mercurian (1755), Venusian (1866), and prior to that I could only assume anything "unwordly" would have simply been referred to as a divine thing, either it be angel or devil, as in Somnium by Johannes Kepler in 1608 or with Milton who hesitantly suggests life on the moon in Paradise Lost, "Stored in each Orb perhaps with some that live." You also have alien-like creatures in The Adventures of Bulukiya from One Thousand and One Nights, but obviously, none of these refer to the being as "alien", and so anyone who would have read these suggestions may have interpreted them as "monsters" or "devils", rather than actual life on any place other than earth, and the influences of the inhabitants of hell and heaven.

Therefore I think it is quite likely that the word "alien" did come up to mean life which is not from earth around the 1920s, which makes historical sense with the advancement of public interest in space, which would of course reach its height in the 1950s/60s with the space race, but regardless, as for my question:

• I am interested if anyone could find anything that would prove the
  word "alien" was used, even if in obscure use, pre-1920s? or if there
  might have been any uses of the word in reference to the cosmic
  pre-20th century?
• and if possible, besides the terms I found like "Martian", etc. which words may have been used in place of "alien" prior to its coinage of meaning extraterrestrial?