Blavatsky, Theosophy & Jack Kirby, Part 1 (1940-1960)

Much of the Theosophical influence in comic books came through popular literature such as Pulp Fiction Magazines of the 1930s. Jack Kirby was an avid reader of Amazing Stories and Astounding.

Weird Tales featured Theosophical elements, notably with  Howard Philips (H. P.) Lovecraft, Robert E. Howard, and Clark Ashton Smith.  Theosophist Talbot Mundy's The Devil's Guard is an example of Theosophical eastern adepts incorporated into adventure fiction.

1940s 

Superheroes were always sort of an unfiltered anything goes grab-bag random mix of pulp culture sub-genres from Victorian era- so all of his fascinations (with Simon) already there Sci-Fi, Horror, supernatural, occult, fantasy, prehistoric.

With Captain America, you have transhumanism (super soldier) and mythologized WW2. Quite a lot of gothic supernatural in early Cap, Hounds of Baskerville, even has his own 'X-Files'.

 

Also in Captain America #1, Simon and Kirby introduced an Atlantis-inspired lost civilisation story. Around 50,000 BC, the cave-boy named Tuk was the son of Phadion and Rhaya, two exiles, and the first offspring of the Inhumans. 

They came from Attilan, the so called "Island of the Gods", in reality a home of technologically advanced humanoids. His parents died in the harsh environment, and Tuk was rescued by the ape-man named Ak who raised the boy to young adulthood. Having reached old age, Ak told Tuk of his origins and urged the boy to find his homeland before dying. Tuk ventured out and was attacked by a group of savage Goreks, only to be rescued by the Cro-Magnon Man named Tanir. The two became inseparable allies continuing along to search for Attilan.

Kirby presents an interesting modernization of Greek Mythology with Mercury in Red Raven Comics #1, 1940.  Another interesting character with alternate reality concepts is The Vision, a very loose of mix of science-fiction, fantasy, horror, occult, crime concepts.  as Aarkus, is an alien law enforcement officer from a dimension called Smokeworld. While Aarkus is looking for a suitable place to exile a prisoner, he is accidentally contacted by Earth scientist Markham Erickson. Leaving the prisoner on the planet Jupiter, Aarkus accepts Erickson's invitation to fight crime on Earth

 The Sandman  in DC's Adventure Comics (#72–97, #100–102) introduced a distinct signature element where villains were plagued by haunted, prophetic nightmares before committing crimes, blending fast-paced urban action with mythic and dream-like threats and occasional occult, mythical, science-elements. 

1950s

The superhero genre, which allowed to blend fantasy genres went on a downturn, Simon & Kirby continue with more supernatural fiction anthologies, ancient aliens, alternate dimensions, psychic/occult, sci-fi.

 

For Harvey comics Black Cat Mystery, Alarming Tales, For DC Comics House of Mystery. With Challengers of the Unknown, a team of paranormal investigator adventurers, prefigures the  space-age Sci-Fi Mythical Theosophical superhero vision that Kirby would bring to Marvel Comics.