It is curious that Achilles here represents courage, when Achilles is normally associated with invulnerability.
The title of Shazam’s book is visible in two panels, but sadly illegible. The characters are likely not from the English alphabet.
If Shazam has been active for 3,000 years, then he predates the Roman names of at least two of the gods who gave him their powers. Since being published by DC comics, Shazam has been depicted as even older and said to derive his powers from different deities than Capt. Marvel, though this is clearly not the case in the original origin. Shazam could hail from the early period of Greece, which seems appropriate given his patron gods, though it is difficult to identify his heritage except that his skin is fair and centuries spent underground could have changed that from any shade. Shazam has been amazingly good at remaining anonymous while fighting evil over three millennia, though he has likely used aliases. Odysseus, Jason, and Beowulf all fit within Shazam’s timeline.
The word “historama” delivers about 53,400 hits in Google today, though it cannot be found in the Oxford English dictionary. It may have been coined here. It would be nice if the historama was the globe, with images superimposed over it, but instead the historama appears to be a flat image projected on the wall, like a movie, only from no visible projector. Again, the fantastic elements are limited to what concepts Billy is able to comprehend at his age, or perhaps by Billy’s level of comprehension.
The historama is a “super-television screen.” The first working television was invented in the 1920s. More advanced, the historama is clap-activated, anticipating the Clapper light switch by about 40 years.
Billy’s “wicked uncle” is not named here and is last seen here for possibly almost eight years, his next known appearance being in Captain Marvel Adventures #88 (Sept. 1948). There are physical similarities between Ebenezer Batson (as he is later named) and Capt. Marvel’s arch-foe, Sivana, and most of their differences are simply distorted characteristics of Ebenezer (Sivana is more bald, has thicker glasses, is more wrinkly, etc.). The concept of a child’s parental figure playing the role of villain in his fantasies can be traced back to Peter Pan, where many stage productions have the father and Captain Hook played by the same actor.
Roy Thomas understood the connection between Ebenezer and Sivana, but simplified it by combining them into one character for Shazam!: the New Beginning.
No explanation is given for how Billy’s parents died. It may have been a recent event for Billy, as he does not appear noticeably younger in the historama as his uncle is kicking him out of his home. That Billy’s father had an intact fortune in money and bonds to pass onto Billy at the height of the Great Depression shows that Billy would have been extremely lucky. Of course, having a fortune willed to you during the Great Depression would have a very common wish. There is accumulating evidence to suggest that Capt. Marvel is not just a wish-fulfillment fantasy, but is specifically part of Billy’s wish-fulfillment fantasy.
In Power of Shazam, Billy's parents are archaeologists and killed by Black Adam (who would not debut in the original continuity for another five years).
P. 5: Shazam says he has spent his life fighting “injustice and cruelty.” Injustice is one of the Seven Enemies of Man. Since cruelty is not one, Shazam may just be speaking in general terms here, or perhaps Injustice was his principal opponent and cruelty is his blanket term for the other six.
By making Billy his successor, Shazam becomes a father figure for Billy.
Billy gains the powers of Shazam by speaking his name. The concepts of magic words and true names having magical power are deeply rooted in folklore.
Billy is transformed into an adult by speaking his magic word. In Power of Shazam, Billy’s father is shown to look identical to Captain Marvel and in Kingdom Come, Billy is shown to look identical to Captain Marvel when he reaches adulthood (through mundane aging instead of magical means). It is a common wish for children to wish to be adults, thinking adults have easier lives.
Although Fred MacMurray is often cited as the inspiration for Capt. Marvel's appearance, the earliest appearance of Capt. Marvel scarcely resembles him at all.
From Wikipedia: Captain Marvel wore a bright red costume, inspired by both military uniforms and ancient Egyptian and Persian costumes as depicted in popular operas, with gold trim and a lightning bolt insignia on the chest. The body suit originally included a buttoned lapel, but was changed to a one-piece skintight suit within a year at the insistence of the editors (the current DC costume of the character has the lapel restored to it). The costume also included a white-collared cape trimmed with gold flower symbols, usually asymmetrically thrown over the left shoulder and held around his neck by a gold cord. The cape came from the ceremonial cape worn by the British nobility, photographs of which appeared in newspapers in the 1930s.
It is also worth noting that the armbands on Capt. Marvel's costume look like bracers, or armor that goes over the forearms, furthering the militant look of the uniform. I think the “flower symbols” look like daggers, but that’s just me. Michael Norwitz says E. Nelson Bridwell had identified the "flower symbols" as moly. Allium Moly does have splayed yellow leaves, somewhat similar to the design on the cape. Moly, of course, also sounds like the "moley" in Billy and Capt. Marvel's favorite catchphrase, "Holy moley!"
Captain Marvel is first named by the narrator, but first hears his name from Shazam. In the ashcan version of Capt. Marvel’s origin, he was to be named Captain Thunder, but the name was dropped over copyright concerns.
Shazam charges him with “sacred” duties, which might be a pun or meant to be taken literally given that gods are the source of most of his powers. “To defend the poor and helpless” and “right wrongs” are democratic ideals, with the former a liberal democratic ideal. Crushing evil, on the other hand, is much more heavy-handed and suggests that the war against the Seven Deadly Enemies of Man is an active one (hence inspiring Shazam to give Capt. Marvel a military-themed uniform?).
That Capt. Marvel calls Shazam “sire” can mean that he recognizes Shazam as his master (Jeff Smith would have Capt. Marvel call him “master”) or can mean that he recognizes Shazam as a father figure (Shazam, in a magical sense, sired him just now).
Shazam has discharged his duty to pass on his legacy to Billy just before being killed, making him the second father figure Billy has lost. Shazam will return, though, as a spirit to guide Capt. Marvel. In Power of Shazam, Shazam does not die and goes back with Billy to Fawcett City.