The Hobbit and The Lord of the Rings are chock-full of interesting races, many of which have become a staple in the fantasy genre. While there's always hostility to be found between them, most seem to live in relative harmony with one another, each laying claim to their own section of Middle-earth. But going back thousands of years to Middle-earth's creation, which race was the first to occupy the land?
Author J.R.R. Tolkien treated his world as an entirely new mythology and, in doing so, created an incredibly rich and complex lore. His writings go as far back as the creation of the universe, with Eru Ilúvatar being the supreme deity above all others (close to Christianity's God). He created Arda, a world that housed a mysterious Sacred Fire at its center. And it was on this world that the land of Middle-earth would be born.
Altered by deities and massive wars between them, Arda was formed into an inhabitable planet. Plants and forests began to grow, and the first animals began to roam around. The land of Valinor (later known to house the Elves) was home to Two Trees of Valinor, which were massive trees that gave light to the land. But across the seas, Middle-earth sat in darkness under the stars, with the first Dark Lord, Melkor, using the area to gain his strength.
Technically, powerful spirits were the first to inhabit Middle-earth, most of which had the power to reshape the landscape. But when it comes to the more traditional races that Lord of the Rings audiences know and love, it was 144 Elves who were first created on Middle-earth. They awoke on the eastern shores over 400 years before the Sun was formed and had to create factions to survive.
As seen in The Lord of the Rings: The Rings of Power, most Elves reside in Valinor. And so understandably, many assume it was Men who first inhabited Middle-earth. But not only did Elves come first, but Men didn't even arrive until thousands of years after them. In fact, Orcs were the next to awaken, as they were bred by Melkor after discovering the existence of Elves.
The first Dwarves are also mentioned around the same time, and some even believe they were created before the Elves. Although, the Elves are the first to be described as "awoken" in Middle-earth. So if the Dwarves did exist, they were not yet walking about the world. But either way, war was soon waged against the Dark Lord, leaving him defeated and imprisoned.
It was now that Elves started sailing over to Valinor to make it their new home, leaving Middle-earth in a somewhat barren state. And for hundreds of years, they dwelled there until finally, the first men awoke in Middle-earth. Much like the time of The Lord of the Rings, it's assumed that Men, Elves and Dwarves were the three primary races, whereas those such as Harfoots and Ents are left with an unknown origin. So summing up the incredibly complicated and intricate timeline, it's assumed that Middle-earth was first home to Elves, then Orcs and Dwarves, and finally Men. But despite this, it's men who end up as the predominant race, many of which believe Middle-earth should be their own.