The world is called Arda, and it is watched over by the Valar and their ethereal servants. That's what the book readers know, but the rest of the pop culture universe refers to this place as Middle-earth, and everyone who doesn't live under a mountain knows the epic tale that took place there, The Lord of the Rings.

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In 1951, Tolkien wrote a letter to Milton Waldmen about the lore of Middle Earth and described the Second Age as "a dark age" that didn't have a lot of interesting history worth describing. He then goes on to describe it for several pages.

When compared to the First and Third Ages, he has a point. However, the Second Age revolves around the rise and fall of Númenor, much of which is alluded to in the LotR movies when the Fellowship comes across an old ruin or sings a song, and there are some worthy tales here that only the book readers know. The new Amazon Prime series, The Rings Of Power, takes place during the Second Age, so viewers might have a chance to catch up to their literary peers once it's released.

6 The Ship Of Eärendil

The Kingdom  of Men in The Lord of the Rings: Rings of Power

The end of the First Age and the transition to the Second was marked by tragedy and loss. Two Silmarils fell into the sea, never to be seen again, and the third was set on the ship of Eärendil, which became a star in the sky. This ended the First Age, and the Second Age began.

Morgoth, who was also called Melkor, was the big bad of the First Age, and he was defeated and cast into the Void. His closest ally and lieutenant, Mairon, remained and sought revenge. He forged a whole family of magical rings to seduce the races of Middle-earth into his service, giving them away as gifts but secretly forged a master ring to rule them all.

5 The Rise Of Sauron, High Priest Of Melkor

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Mairon became known as Sauron, and it was his malevolent influence that eventually caused the fall of Númenór from within. It was not until the year 500 of the Second Age that he returned to power, and it was not for another 500 that he even started to build Barad-dûr, which would serve as his major headquarters for the rest of the Second Age and well into the Third.

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Sauron's power was more about lies and manipulation than using force, and he did more damage as the High Priest of Melkor and the closest advisor to the Númenóreon king than as a military commander. Sauron started an evil cult dedicated to Melkor, in which his followers worshiped dark powers and rejected the Valar, which is partly why Eru Ilúvatar destroyed Númenór.

4 The Destruction Of Númenor

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There's a fair amount of lore regarding the Kingdom of Númenor, and most of the action earlier in the history of the Second Age takes place on this lost continent. The Valar gave the island nation to certain human rulers as a reward for helping them defeat Melkor on the condition that they do not sail back towards the land of Aman. The people of Númenór were content with exploring and colonizing Middle-earth and prospered for centuries.

However, Sauron persuaded the aging emperor Ar-Pharazôn to break the Ban of Aman in an attempt to find eternal life, and the price for this betrayal was a high one. The most powerful of the Valar, Eru Ilúvatar, sank Númenór and imprisoned Ar-Pharazôn and his army for all eternity. After Númenór was destroyed in the year 3391, the last vestiges of the old nations and races that survived moved permanently to Middle-earth.

3 The First Ships Sailed To Middle-earth

Nurn in Middle-earth: Shadow of Mordor

Men and Elves sailed to Middle-earth well before Númenór was destroyed. The first ships sailed to Middle-earth from the ancient island kingdom as early as the year 600. Eregion, an ancient Elvish kingdom that was the home of Galadriel and Celeborn before Lothlórien was established, dates from the year 750.

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The Grey Havens was established in the very first years of the Second Age, along with the Elvish kingdom of Lindon that hosted it. It was a common destination for ships traveling from Númenór and for Elves that had chosen to live in Middle-earth after the fall of Morgoth and the end of the First Age.

2 The Forging Of The Rings Of Power

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The Rings Of Power were forged late in the Second Age, in the year 1500. Sauron influenced the Elves at this time and convinced the master smith Celebrimbor to help him, although Sauron made the Master Ring in secret for himself a year later. It was trickery and greed, not martial might, that Sauron used to make the people of Middle-earth his slaves.

The plan had a few wrinkles, however. As soon as Sauron put the ring on his finger, the Elves sensed his presence and removed theirs. The Men and Dwarves were not as strong. Those that were tempted by Sauron's promise of power and wealth or those that thought they could withstand his influence, would wither into the Nazgûl, who appeared in 2251 of the Second Age​​​​​.

1 Celebrimbor And The Three Rings

Galadriel in The Lord of the Rings: Rings of Power and The Hobbit

Not all the magic rings in Middle Earth were under the power of Sauron. Celebrimbor wasn't just any old smith. He was the grandson of Fëanor, the crafter who had made the Silmarils, and he suspected that Sauron was up to something. That's partly why he hid the Three Rings that he had crafted for the Elves himself, so they would not fall under the Dark Lord's influence.

These rings appear in the movies even though viewers might not take note of them and don't know their origins. Narya is the Ring of Fire that Gandalf wears, Nenya is the Ring of Adamant that has always belonged to Galadriel, and Vilya, the Ring of Air, was eventually inherited by Elrond.

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