Sauron is a curious foe. The eponymous Lord of the Rings is the overarching antagonist of J.R.R. Tolkien's epic fantasy trilogy. Despite that, audiences don't know much about him aside from his creation of the One Ring and desire to dominate all life. The heroes of the tale actually spend more time contending with Sauron's servants than the Dark Lord himself. This aids in the malevolent mystery surrounding the character.

RELATED: Most Immersive MMORPGs

However, Tolkien crafted a vast history for Middle-earth and its residents, Sauron included. Among the most extensive sources for such backstory is The Silmarillion. This book details the formation of the world, the emergence of its various beings, and the conflicts that follow. Sauron is a key player here. Those who dive into this biblical tome will learn things about the villain never thought possible in the mainline Lord of the Rings trilogy.

7 He Was Second-In-Command

Morgoth and Sauron in The Silmarillion

When people picture The Lord of the Rings, they think of Sauron as the grandmaster of all villainy. Indeed, he is the main antagonist of the iconic story. However, that wasn't always the case.

In ages past, Sauron was subservient to Morgoth, who is basically the Middle-earth equivalent to the Devil. He was one of the Valar (gods) who succumbed to jealousy, ambition, and malice. This led him to betray his kin and lead a long, bloody war to conquer their collective creation: Middle-earth. Sauron was Morgoth's top lieutenant in this endeavor. He even managed his master's armies while the fallen deity was away. Once the other Valar overthrew the Dark Lord, Sauron assumed his mantle.

6 He's The Same Type Of Being As Gandalf

Gandalf and Sauron in The Lord of the Rings

Sauron is one of the Maiar. These are spirits who serve the Valar and facilitate their will. Morgoth corrupted several of these beings. Many of these became fiery demons known as Balrogs, but Sauron was different. He was chief among the villain's servants, equipped with more abilities and autonomy to complement his deviousness.

RELATED: Harrison Ford & Other Actors Who Played More Than One Iconic Movie Character

After vanquishing Morgoth, the Valar sent five more Maiar to safeguard Middle-earth. These manifested as Wizards like Gandalf the Grey, Saruman the White, and Radagast the Brown. It's not surprising that they later came into conflict with Sauron.

5 He Battled Beren And Lúthien

Beren, Huan, and Luthien in The Silmarillion

These star-crossed lovers became legendary for their devotion and determination. The romance between Man and Elf itself was a precursor to Aragorn and Arwen's relationship in the main tale. This love story played out differently, though.

Reluctant to allow his daughter's marriage, King Thingol tasked Beren with retrieving one of the Silmarils from Morgoth's crown. The rugged underdog was soon intercepted by Sauron, who imprisoned him on his torturous isle. Fortunately, Beren was freed thanks to the efforts of Lúthien, who bested the dark servant through enchantment, misdirection, and help from a friend.

4 He's A Werewolf...

Sauron, Huan, and Luthien in The Silmarillion

Sauron's method of waylaying Lúthien was strange. He had already conquered the land of werewolves and sent several of these after the She-Elf. When they failed, he turned into a wolf himself. Sadly, the ensuing battle was more than he bargained for.

The malicious shapeshifter had to contend with both Luthien and Huan. He was a wolf created by the Valar and sworn to serve the Noldor Elves. This killer canine was more than a match for Sauron's cheap imitation, and his and Lúthien's combined efforts were enough to beat the baddie back.

3 ...And A Vampire

A Vampire in The Hobbit: The Battle of the Five Armies

Following his defeat at the hands of Lúthien and Huan, Sauron needed a quick getaway. Thus, he turned into a vampire and flew off. In Middle-earth, these are bat-like creatures who serve the dark forces. Ironically, though, this was one monster that the bad guys had a short supply of.

RELATED: Skyrim Special Edition: Mods To Transform It Into A Lord Of The Rings Game

One of the only major examples is Thuringwethil, who herself was a thrall of Sauron. The Dark Lord possibly learned from this in crafting his own vampire form. After all, he was always a master of deception, and shapeshifting was a big part of that. He'd naturally take every advantage he could get.

2 He Started A Sacrificial Cult

Sauron in The Silmarillion and Middle-Earth: Shadow of War

When the Men of Númenor came to Middle-earth to wage war on Sauron in the Second Age, the Dark Lord saw that he couldn't overcome his enemy by force. So, he surrendered himself to their superior forces and went back to their island as a hostage. This lowly status was not to last.

Sauron soon became a trusted advisor to the king and official figure among the people. He convinced many Numenoreans to forsake their faith in the Valar and worship Morgoth instead. He even built a temple for his master, offering human sacrifices in tribute. It just goes to show what a silver-tongued devil he was, but he wasn't done yet.

1 He Brought The Fall Of Númenor

Numenoreans in The Lord of the Rings: The Fellowship of the Ring

During his time in Númenor, Sauron continued to sow seeds of doubt and contempt for the Valar. He made the Men question why they didn't have the immortal life granted to the Elves. Coveting such things led to their greatest mistake.

The villain finally persuaded the Numenoreans to sail to the Undying Lands. There, they would enjoy the blessed life of the Valar and Elves, taking it by force if needs be. This led Eru Ilúvatar, the supreme creator and father of the Valar, to intervene for the first time. He changed the shape of the world, put the Undying Lands forever out of reach, and sunk both the Numenoreans' fleet and island. Sauron was severely damaged, but he had successfully destroyed his enemies from within. Thankfully, the story has a silver lining.

The survivors--Elendil and other Valar loyalists--escaped to Middle-earth and formed the kingdoms of Arnor and Gondor. They then allied with the resident Elves and defeated Sauron. Thus, the stage was set for The Lord of the Rings.

Illustrations by artists John Howe and Alan Lee.

MORE: Highly Anticipated New TV Shows Coming Out In 2022