I spent far too long examining almost every. Single. Maxwell quote on the Wiki and have uncovered some interesting things that only either 1) Maxwell Players or 2) Others who have spent an hour looking at Maxwell's quotes (Wait... Who else DID THIS?) will know. So sit back, and be educated! (Eh... more or less...) This list is in no particular order.
1) Maxwell knew Lucy. Could lead to speculations on how Woodie and Maxwell relate ("Ah. How have you been, Lucy?")
2) Most any Maxwell player has probably noticed that Maxwell calls the World of Don't Starve's moon- "The 'Moon'" ( "The gem conjures water springs in conjunction with the "moon's" cycles." )
3) The Ruins of the Ancient's city has a pulse, apparently. How odd, as Nightmare Fuel has been described as "still warm" by Willow. Odd, as animals with warm bodies are considered to have been alive, at some point. Alive. Alive. ("The pulse is quickening." -Thulecite Medallion (rising high))
4) Maxwell refers to the Houndius Shootius as his own work. Why would he make it? What does he have to protect himself from? He knows he cannot be killed upon the nightmare throne. But perhaps it is the one thing that likely can kill him upon the throne he fears... Also, he (spoilers for later facts) is know to be friends with the Ancient Guardian. So why does it require Ancient Guardian to be dead to make? Although, I suppose Maxwell may not have needed the ingredients. But then why would the Ancients have it in their Pseudoscience Station, if Maxwell made it. And why would it require the Horn of the Ancient Guardian. As in... GUARDIAN of the ANCIENTS... Who knows... ("Some of my better work.")
5) Maxwell must have known the Dragonfly before, when it... was young? Or some similar creature, as the Broodling, upon examination, explains "Just like old times"
6) Heavenly Eggnog is Maxwell's favorite, he proclaims. He seems completely touched by the fact that he believes Charlie, who was ruling the nightmare throne at the time, added it for him. This honestly was touching, even to me, when I saw this quote... ("My... favorite... she remembered.")
7) Maxwell says there is a story behind the Touch Stone and its' existence. How odd, I'd like to hear... ("There's a story behind that...")
8) The "Headless Harp Statue" was made by Maxwell, although unlike the Clockworks, he isn't too proud of it ("Not my best work"). However, the Marble Pillars weren't created by him, and he doesn't even know who by. ("I've always wondered who built those")
9) Maxwell remembers every past explorer he comes across. This means either the surface was uninhabited until Maxwell arrived, or the only other human remains have long since past decomposition of even skeletons... So yeah, probably the first... ("Ha! I remember that one.")
10) Charlie's personality is hinted in the Florid Postern... Not that any Maxwell player hasn't noticed ("Always did have a flair for the dramatic...")
11) In relation to the Moon Stone, he has some interesting comments to make. He says "Ruins of an ancient relic." in relation to the non-repaired Moon Stone. This gives me two ideas- the usage of "ancient" is likely not referring to the Ancients, as it is non-plural and lowercase. This does show, however, nearly for certain that the Don't Starve World existed LONG before Maxwell. Also to aid in this idea is that the repaired Moon Stone has a different quote, "I had thought these were all destroyed eons ago."
12) "I plugged it a long time ago." (Plugged Sinkhole) "That was not a good idea!" (Opened Sinkhole) "Get me out of here!" (Rope to surface from Caves) Well then, Maxwell, we know something isn't too great about the Caves... What are you hiding?
13) Ancients SPEED ROUND: (Nightmare Light) "The overuse of fuel was their downfall", (Ancient Statues) "A once proud race.", (Ancient Pseudoscience Station {broken})- "This can be partially restored.", (Ancient Pseudoscience Station {repaired})- "Where are their gods now?", (Ancient Chest)- "A relic best forgotten.", (Ancient Mural {first})- "A picture of the city, before the fuel.", (Ancient Mural {second})- "We all know that happens next.", (Ancient Mural {third})- "They gained such an enviable power…", (Ancient Mural {fourth})- "I know why you led me back here.", (Ancient Mural {fifth})- "But it won't work."
14) Fun Fact: Fire and Ice hounds are Hounds Maxwell stuck a gem in either "as a joke" or due to a surplus or gems. ("I put fire gems in there as a joke." and "I had a lot of surplus gems!") Also, Hound Mounds go to the underground Hound Nests ("It's a tunnel down to the hound nests.")
15) Swamp SPEED ROUND: (Rundown House) "They copied the pigs, but they're even less intelligent.", (Merm) "They were here when I got here.", (Tentacle) "I'm glad the rest of it is still down there.", (Tentacle Spots) "This is how they reproduce.", (Tentapillar {Big Tentacle}) "How deep does this go?"
16) The ghosts remember Maxwell... No wonder they attack! ("It remembers me!")
17) Maxwell also seemed to know the MacTusk, as he seems friendly towards it, but it seems to not remember him. ("Don't you recognize me?")
18) Dangling Depth Dwellers were apparently different In-Game from Maxwell's last check on the Caves- He claims they change at a terrifying rate! ("Creatures in this world evolve at a terrifying rate.")
19) Depth Worms are apparently new to Maxwell, more proof of the quick evolving species ("Well that's new!")
20) Rock Lobsters were once on the surface. Maxwell claims he banished them to the underground, for a reason. ("I banished these guys down here for a reason.")
21) Ahhh, time to cover the great bird mystery. I'll just shove all of this into one fact. Are you ready? Ahem... Maxwell doesn't know much about the birds. He proclaims he doesn't know how the Crows got there, that the Redbirds come from the firelands, likely a land we haven't explored, and that the Snowbirds are just completely new to him. (Crow- "I don't know how they got here.", Redbird- "The redbird comes from the fire lands.", and Snowbird- "I don't recognize that one.") Also, apparently Maxwell doesn't like the Canaries, as his quote sounds like confused disgust ("How do these things keep getting into my world?"). Tallbirds are seemingly a genetic experiment, a failed one at that. ("These were a failed experiment."). Perhaps it was to do with the uncertainty of the birds? Also, Tallbird nests are made of dirty Beefalo hairs...
22) Maxwell knows about Chester's strange resurrection abilities, or that there are more Chesters, as he says to a Eyebone turned to dust, "Don't worry. There will be more Chesters."
23) Maxwell was seemingly great friends with the Ancient Guardian. The Guardian was likely very different when Maxwell knew him, as he proclaims "My my, the fuel has changed you." And when the Guardian dies, his horn's examination says "I'm sorry I have to do that, old friend." Even more saddening is when Maxwell examines the Large Ornate Chest, which appears when the Guardian dies, he says "It's almost like he's still alive." He misses his old friend, huh?
24) Green and Orange Gems seem to be prone to Nightmare Fuel (Green Gem- "The nightmare fuel will unlock its true potential.", Orange Gem- "This will be quite powerful with some fuel."), How funny, considering these are gems in the ruins. And the Desert Stones are claimed to be "An impure orange gem.". Could this mean that the lack of fuel it has received from being with the Antlion made it this way? And also, how did the Antlion get an orange gem? Aren't they from the Ruins?
25) The Obelisk only half-exists on the plane we're in when we play Don't Starve. I suppose, since it is theorized that the shadows like Mr. Skits and the Crawling Horror are only half on our plane, only accessible when we go crazy. Perhaps that is how Obelisks can rise and lower, with Mr. Skits popping in and out of it to rise and lower it. ("It only half-exists on this plane")
BONUS: (Frayed Yarn- "The monster child gets tangled in this frequently.") Can anyone else imagine Webber playing with the Yarn? And getting tangled? WOULD THAT NOT BE HILARIOUS?
If I missed anything, or if you think something else should be added, then please tell me!
And if you actually read all of these quotes and my minor theories, then please, do tell! (And you earned a gold star!)