Sauron gave the Seven Rings to Dwarf-lords to control them, but they resisted his domination, instead becoming immensely wealthy and greedy, which attracted dragons and led to ruin. While Sauron couldn't enslave the Dwarves like Men, he recovered some rings, and the others were lost to dragons, ultimately bringing doom to the Dwarf-clans, though none became wraiths like the Men who wore the Nine.
The Seven given to the Dwarves failed to subject them directly to Sauron's will but ignited a sense of avarice within them. Over the years, Sauron sought to recapture the Rings, primarily the One, but was only successful in recovering the Nine and three of the Seven.
It is said that thanks to them the Seven Hoards were made. But also the Rings kindled greed and wrath in the Dwarves, bringing evils that in the long-term benefitted Sauron. Four were consumed and destroyed by Dragons, but Sauron succeeded in finding two.
For the elven rings, he didn't touch the mithril at all during forging, or the rings themselves, leaving them unsullied. For the dwarven rings, he held and presumably cursed the mithril before adding it to the crucible.
In time, the nine Men to whom the Rings were given became Ringwraiths, or Nazgûl, wraiths of great power under the command of Sauron. The Dwarf lords to whom the Seven were given became wealthy beyond measure, but they did not fall to Sauron's power.
All the rings did was to fuel the greed of dwarves and they served themselves, rather than fall under control of Sauron, although their greed led to their downfall, they were still not under control of sauron, that's why Sauron wanted the 7 rings brought back to him.
Whatever happened to the dwarves was recorded in that large tome, which can be found in the chapter “The Bridge of Khazad-dûm”. There was no communication between Balin's group and Erebor before this so there was no way Gimli, or anyone else, could have known about it.
The Ring's effects
Inversely, the hobbits' good-naturedness and lack of ambition makes them less susceptible to the Ring's promises of power, as in Frodo and Samwise Gamgee, who are able to handle the Ring for extended periods of time.
Sauron's rise to power in the Second Age is portrayed in the Amazon prequel series The Lord of the Rings: The Rings of Power. He first appears disguised as the non-canonical human character Halbrand, and then in the second season as Annatar (a canonical alias of Sauron), both played by Charlie Vickers.
It's not the years; it's the mileage. Gandalf isn't a Maia in the same way Sauron is. He was sent to middle earth as an old man, so his body is much more real than Sauron's “raiment”. He can't use his power to the same extent, he can't change his forms at will.
If Gandalf had stayed dead after his sacrifice in The Fellowship of the Ring, then his demise would be the saddest in the trilogy, but since he came back, the saddest single death scene of all three movies goes to Boromir's.
Why did Fili and Kili have to die? There are a few different theories as to why Tolkien had Fili and Kili die at the end of The Hobbit. One theory is that he was emphasizing the important and loyal role that Fili and Kili had as sister-sons of Thorin, an important relationship in medieval literature.
After the battle, the Arkenstone was placed by Bard upon Thorin's chest within his tomb deep underneath Erebor, and so was returned to the earth at last.
Canonically, Balin is the only dwarf from the The Quest of Erebor that is mentioned as visiting Bilbo after he returns to the Shire but based on the number of mentions of dwarven visitors to him over the years I'm sure a few of the others may have come back West at some point, in addition to other dwarves who knew him ...
It's possible that Gollum's prolonged search for the ring allowed it to maintain a significant power over him, suspending his aging process. In contrast, Bilbo's exposure to the ring's influence waned after he willingly (mostly) relinquished it, allowing his aging to resume more noticeably.
As a Maia, Gandalf was an angelic being in human form, in service to the Creator (Eru Ilúvatar) and the Creator's 'Secret Fire'. He took on the specific form of an old man as a sign of his humility. His role was to advise but never to attempt to match Sauron's strength.
Tolkien's description of Gollum conforms to a Catholic – and Thomistic – account of envy, which is a “sadness of the soul”; and it is Gollum's unbearable sadness and his unquenchable desire for the one Ring that marks his character.
Elrond chose the fate of the Elves and therefore the choice was presented to his children. The reason why Eldarion and his sisters (the children of Aragorn and Arwen) were born mortal was because Arwen chose mortality and therefore that fate was passed on to the rest of their line.
He did not trust Gollum, for he divined something indomitable in him, which could not be overcome, even by the Shadow of Fear, except by destroying him.
In the books, Legolas actually screamed in terror when he realized that a Balrog was coming. It was the Balrogs that rounded up the elves for Morgoth, to be corrupted into orcs.
Frodo left Middle-earth due to lasting injuries from his journey, seeking healing in the Undying Lands. His decision was influenced by trauma and a desire for peace, similar to Tolkien's own experiences. In Rings of Power, Frodo is portrayed as a hero who found solace and closure in the Undying Lands.