The swords, magic rings, and heroic deeds are just decorations in the vast and epic world of Arda, the setting that Tolkien created for The Lord of the Rings and many of his other stories. Arda is part of a whole network of continents, a pantheon of gods, and even a separate plane of reality called the Void.
The Elves called it Arda in the Quenya tongue, and this whole universe of which it is a part is called Eä. The includes places like Valinor, Numenor, and the Helcaraxe, which are locations from ancient history. Places like the Shire, the kingdom of Gondor, and all of the other famous places featured in the LotR are also a part of Arda. Tolkien intended for this world to be the real focus of his stories, which is why he included characters like Tom Bombadil, who had nothing to do with the Ring of Power.
5 Originally Flat
Arda doesn't look the same as it first did when the Elves first awoke in the forests of Valinor. On a map, it would look like a flat plate surrounded by water, and the Encircling Sea was called Ekkaia. The continent of Aman, which would be the Undying Lands in the future and was the location of Valinor, was in the western part of the continent.
The eastern side, which would be Middle-earth in the future, was known as the Hither Lands at that time and was home to a vast forest that would eventually become Mirkwood, Fangorn, the Greenwood, and other woodlands when the world was changed. It was the War of the Powers, the first conflict with Melkor, that separated and formed many of the places that the heroes would visit in The Lord of the Rings.
4 The War of Wrath
The second time a war with Melkor caused Arda's geography to change was the War of Wrath. This is also known as the War of the Jewels, the main motivation being the recovery of the stolen Silmarils, and the damage caused part of the continent to sink into the sea. This part of the world was called Beleriand, and it was a kingdom of Men, which is why the Valar rewarded them with the island of Númenor as compensation.
Some of Middle-earth remained and survived, and there was still plenty of room for Elves, men, and eventually Hobbits in what remained. Regardless of the amount of ruin, the remaining lands would enjoy hundreds of years of relative peace without the influence of Morgoth or Sauron.
3 The Raising And Sinking Of Númenor
The kingdom of Númenor flourished for centuries. The first king, Elros, was one of the Half-elven, a descendent of Luthien, and the prosperity came from his kingdom's close relationship with the Elves. A seed of dissent had been planted, however, in the form of a Maiar who resided in Numenor and was a close advisor of its leaders.
Following the War of Wrath, instead of returning with his master Morgoth to face judgment, Sauron hid quietly in Numenor and shared his vast knowledge with the people there. He turned the rulers away from the Valar and the Elves, counseling them instead to conquer the Undying Lands and take immortality for themselves. The result is what is known as the Akallabêth in the literature, or the Downfall of Númenor.
2 Dragons And Other Unique Fauna
The dragons of Arda are few, but they're extremely dangerous, and they've had an important influence on the world's history. Overpowered versions of conventional European dragons, the ones that appear in LotR lore are second only to Balrogs in terms of their malevolence.
Morgoth originally made them from other creatures while in exile, but not all of them were loyal to him or Sauron, and this is the closest the reader gets to any kind of origin story for dragons in Arda.
Dragons were always used by the villains of the series, with the attempt of Sauron to recruit Smaug in The Hobbit being the most famous example. He was one of the most powerful types of dragon there are; an Uruloke, a Fire-drake of Angband. Glaurung, a dragon of the same order who was even more terrible than Smaug, was slain by the tragic hero Túrin Turambar.
1 The Constellations
The arrangement of the stars above Arda is the same as real life since Tolkien designed this world to be another version of the real one. The Sickle of the Stars, for example, is Ursa Major, also known as the Big Dipper. The kingdom of Numenor is shaped like a star, perhaps as a symbol of protection as well as a reminder that it was a gift from the Valar.
The Elves hold certain constellations in high regard, saying that the boats follow the straight path through the stars to the Undying Lands, but they aren't named very often. Rings of Power makes the stars a more important part of the story with Nori's mysterious human friend, who seems to be looking for a location under a certain group of stars.