WMG / American Gods

Shadow isn't the Baldr
That was a full god, and Shadow is only a demigod. There is a running theme of one thing being two and two things being one in the American Gods continuity, so Shadow could easily be a demigod who was ironically (the intentional version of irony) given the same name as his Deader Than Dead half-brother, and accidentally stepped into his half-brother's place in thingspicking up a few extra tricks along the way.
  • Mr. Wednesday is canonically just the American incarnation of Odin, as shown by the Icelandic Odin's appearance in the epilogue, so logically his son Shadow is the American Baldr.

The book and the twitter are an attempt to restore faith in the gods.
After the battle the new and old gods were too weak to exist without some additional belief, so they first got Neil Gaiman to write the book and later the god of social networking started the bookclub on twitter to keep the interest in the book high.

As a corrolary, this book was made by the New Gods to ensure their survival
Possibly the reason the Old Gods continue to survive no matter what, while the New Gods die when the thing they repersent go out of style, is because the stories of the Old Gods are still being told. Smithing may not be as mainstream as it used to be, but as long as people continue to pass down stories he is in (such as the origin of the Greek gods), Vulcan will still survive. Railroads didn't have that advantage, so he died when not enough people took the train. Cars will not have that problem, so long as people read this book.

The two guesses above are both true; additionally, the whole idea was Wednesday's Plan B
Because logic dictates that a Bastard as Magnificient as Wednesday can't go without contingency plan. He had made arrangements so that when Shadow stopped the two fighting forces and his "war" went downhill, a record of the whole thing is delivered to Mr. Gaiman. The resulting faith brought forth by the finished novel was enough to nourish both the Old and New Gods and resurrect their dead (including Wednesday and Loki). Wednesday could then claim this is what he was aiming for all along, honest.

Mr Wednesday is Just Hiding.
Although Shadow stopped the battle proper, gods still died in the opening skirmish, including between Shadow finding out itís a con and talking to the dis-embodied Wednesday and stopping the battle: possibly enough to fuel Wednesday's resurrection. Given his plan was scuppered by Shadow before he could gain full power, he decided to lie low and play dead.
  • Jossed in the text. Not only does Mr. Wednesday say it had to be a real death, one of the death gods present points out that it simply wouldn't have been possible to fool him about something like that; part of his powers let him confirm for a fact that Wednesday was dead.

Bast took over The Internet's position after the latter's death.
It explains the popularity of LOLCats.
  • I like that. Besides, Bast is too awesome to die.

Loki is/was J. Edgar Hoover.
He infiltrated the FBI during its earliest stages and cultivated it into something iconic. While in a position of power, he also engaged in randomness and rumor mongering so that people would still talk about the scandalous little details to this day - up to and including the belief that Hoover had nude photos of Elanor Roosevelt "just in case".

At the same time, he actively worked against the reputation of that individual organization in preparation for his retirement, making sure to discredit it and any of its successors. Which would mean that he was the one who first told the CIA joke. By doing this, he was able to build up a suitable MIB mystique in American consciousness that it manifested the New-Gods-aligned organization that we all know & hate. Using his experience as Hoover, Loki took control of the organization and was able to reap the benefits of having an army of disposable little gods that are easily dealt with when faced with a Tomato in the Mirror moment.

This is why Mister Town & co follow his orders. They know that he was Hoover before becoming Mister World, and that's explanation enough for them. The higher-ups always know better & are more scarily-competent. Even when the higher-ups are in jail.
  • The fact that he named the organization after an anagram of "Fib" (a synonym for "Lie") is supposed to be a subtle raspberry to his enemies.

Lakeside is Lake Wobegon
Both are towns (beside a lake) in the Midwest that have thrived despite the depopulation of the rural Midwest. There are several other similarities, such as the genial and occasionally eccentric inhabitants.

The god in Las Vegas was Binbougami, the Japanese spirit of poverty
Explains why he gets empowered by the loss of wealth and why he would request Soma as his price.

Low-key has some connection to Verbal Kint of The Usual Suspects

Let's see- Scheming character with multiple identities, one of which is the persona of a two-bit con artist. Both arrange their arrest so they can meet up with people in prison. The two admittedly look pretty different, but some amount of disguise going on seems pretty plausible.

American Gods and Eight Days of Luke take place in the same continuity.

Gaiman has said he was inspired by Diana Wynne Jones, and Luke and Wedding have very similar personalities to Low-Key and Wednesday, just toned down a little for a children's book. Also, at the end of Eight Days of Luke, Wedding mentions battling other faiths for belief. And the Valhalla hidden inside a funfair is similar to various settings in American Gods.

Thor is alive because they're the British versions, not the American ones, and are doing a little better (or were back in the seventies.)

American Gods takes place in the same universe as Percy Jackson and the Olympians and The Kane Chronicles

The Greek/Roman Gods were smart enough to know that if they didn't somehow keep themselves known, they too would fade. So they did what they needed to in order to ensure their survival, and moved to America, had a bunch of children that they claimed and put into a camp, and told them to worship their parents (the Gods) all summer and throughout their lives. Unfortunately, because of the strong concentration of power focusing on not only the Gods, but also the monsters that came with them, their children accidentally brought the Greek/Roman monsters to life as well. The reason we don't see many of the Greek/Roman gods around Shadow is because they're busy with their own troubles that don't include fading out of existence.

The Egyptian Gods had a different idea and decided that if there weren't enough people to worship them into a physical existence, that they would need to take hosts. So they did. The rest who could have a physical form appear much like Mr. Wednesday did to Shadow; in a human form that best matches their personality.
  • Is it possible that the Egyptian Gods actually [i]entered[/i] the immaterial plane itself, and actually live there now, thus becoming independent from worship, but only able to leave in brief jaunt without a host?( In case you forgot, Wednesday mentioned that humans are drawn to "holes into the immateriam", and that we built our temples there, so it makes sense that that's where the metaphorical 'nectar' we use to make the 'honey' that is prayer that the gods live off of.) Theoretically, if they went to the source of power itself, they'd be independent from mortals. If they found out a way to enter and consume the 'nectar', why wouldn't they?

American Gods takes place in the same multiverse as The Sandman
Neil Gaiman aside there was a blink and miss it cameo by Delirium.
  • After failing to buy Hell from Dream (and Loki escaping) Odin decided to come up with a different way to survive Ragnorok.

The Lakeside sub-plot was inspired by the Blue ÷yster Cult song Harvest Moon
If you've read the novel and heard the song, the similarity is blindingly obvious.

I don't believe that BS about Thor committing suicide — dude's playing lead guitar in a folk metal band, and simply has no interest in the shenanigans of the novel. He's doing quite well enough, thank you, from room-fulls of people with hammer pendants/tatoos mosh while singing along enthusiastically to lyrics that mention him either directly or indirectly.
  • Option 2: he doesn't care, because he's one of the more relevant gods to popular culture. He was just hanging around the Marvel offices, secure in the fact that people are still worshiping him, every time they buy a comic bearing his name. And the blockbuster movie only made him stronger. (Loki may have been in on that last one).
  • This also explains why Odin would SAY Thor committed suicide. What Thor really did was go to the side of the New Gods, because through them, he was being worshipped. Still, Odin saw that as betrayal and would rather think of his son as dead than think of him as a traitor.
Thor was drastically weakened by the harnessing of electricity, and the popularization of the science behind lightning and thunder did him in.
  • Thor was once a warrior god. If he became so weak that he could barely exist anymore, he might well have killed himself rather than fade away slowly.
  • The belief that has gone to Thor in the past has now gone to the invisible god/goddess, one so powerful that we never see him/her, and who is the parent of Media: Electricity
    • All Americans know how powerful and dangerous electricity is, and when there is a power outage at night modern people have an almost prayer-like hoping and pleading for the power to come back on, especially when it is cold outside (as it is in most of America's population centers for much of the year).
  • Thor's suicide was a resurrection gambit. While he's most known for being a warrior god, he was first of all a fertility god, and they're pretty well known for having a more casual relationship with death than the average Joe. Thor could see where Odin and Loki's machinations were going to lead (even if he didn't know what they were planning, he could tell it was gonna be bad) and so got out while the getting was good before he could be made into a pawn like his brother Shadow would be. He's a lot smarter than he lets everyone else know, as can be clearly seen in the Lay of Alvis, and cultivated a big-dumb-guy persona so that Odin and Loki would always underestimate him. He committed suicide, resurrected himself as someone else, and kept his/her/whatever his new identity was on the down low so he could avoid being caught up in the kerfluffle to follow.
    • Wednesday notes that Shadow is a lot like Thor, big, kind-hearted, dumb. I know he's supposed to be Baldr, but a lot of mythological figures have become Composite Characters over time. It's also noteworthy that the first hint that Shadow had some supernatural power was when Wednesday had him make it snow.

The events of the book, for the most part, did not take place in any non-metaphorical sense. But the gods themselves are real.
This is said pretty verbatim in the book more than once, but I'm putting it here as another perspective on the potential Magnificent Bastard plans Odin made. Perhaps with Odin's influence, perhaps not, Mr. Ibis may have been integral in the book's writing (Gaiman may or may not have known about this in the process). His histories, as mentioned, are not necessarily literally true, but they are written to reveal a truth. And in ancient times, weren't stories of the gods originally written by divinely inspired men? Care was probably taken to flesh out the characters of the American gods as much as possible, and the plot (as interesting as it was!) may not have happened to them at all. After all, it's a metaphor for ancient beliefs struggling to survive in the era of technology, isn't it? The book takes care to mention that the literal truth and the metaphorical truth are vastly different and yet are one and the same, when it comes to the gods and other creatures like the thunderbirds. In sum, the book was written through the influence of at least some of the gods to inspire belief about them, as said above, probably through the meddling of gods like Odin. But everyone else might have been on board with the idea, too.

Loki is reincarnated in the wake of the recent Marvel movies.
He now has millions of fangirls worshiping him, praising him, writing about him, dressing as him, making images of him, lusting after him. Only now he has black hair instead of red and resembles Tom Hiddleston.
  • Tying in with the above guesses about Thor — he was always a god associated strongly with the 99%. Maybe he really did commit suicide in 1932, which would have been not only roughly the low water mark of his following in America, but during the teeth of the Great Depression... but then was also reincarnated in 2011 when he suddenly gained popular interest and approval again.

American Gods takes place later in time in the same universe as The Brothers Karamazov.
Though he claims to be a ghost the whole time for the fun of messing with the atheist Ivan's head, Satan is genuinely the Russian Satan in exactly the same way that Wednesday is the American Odin (and this version of Satan is amazingly similar to Wednesday, though probably worse). The description of him as looking like the kind of guy who would always be a begrudging guest of the elites is so American Gods-like that it reads like it was somehow plagiarized through time and space. Plus, the deleted scene from the book shows that figures from the Bible aren't exempt from appearing with all the other gods.
  • Given the way Father Zossima is treated as being able to cause minor miracles and the whole town is thrown into an uproar by the unusual circumstances around his death, he might also be the modern version of some now-forgotten local pre-Christian spirit, like a good version of Hinzelmann.

The character Burt Reynolds played in The X-Files episode 'Improbable' is the American incarnation of God.
He could even be a New Gods incarnation of God.

At some point Kek will appear on the show
He's an obscure Egyptian god who has experienced a recent surge in popularity on the internet due to conflation with Pepe the frog. He will most likely side with the new gods, especially the technical boy.