Erebor

Erebor, also known as the Lonely Mountain is a major location in The Hobbit (film series). It is the greatest kingdom in Middle-earth. It was located in northeast of Rhovanion, and was the source of the River Running.

Years of the Trees and First Age
The Dwarves of Durin's Folk discovered the mineral wealth of the Lonely Mountain sometime after the awakening of the first Durin. A mining colony was soon set up and the Old Forest Road was laid out to connect the Dwarves to their great cities from the Iron Hills and as far west as their realms and possessions in the Blue Mountains.

In the Beginning
The Dwarves may have lived and mined in the mountain during the Second Age, but it wasn't until the mid-Third Age that the colony had become a firmly established Kingdom of the Dwarves after the fall of the ancient Kingdom of Khazad-dûm due to the awakening of the Balrog later known as Durin's Bane in T.A. 1981.

The survivors under Thráin I followed him to the Lonely Mountain and the colony became the ancestral home of the King under the Mountain. By T.A. 1999, it had become a Dwarven stronghold, where the Dwarves became a numerous and prosperous people. In this time, the Dwarves became very rich and amassed a large amount of gold and treasure which included the jewel known as the Arkenstone. Thrain I used the Arkenstone as a symbol of his rule, and his sons and grandsons under him who were to follow.

For nearly two-hundred and eleven years, the kingdom advanced, expanded, prospered, and endured until Thorin I abandoned it to join his kin in the Grey Mountains, and the Lonely Mountain was abandoned for three-hundred and eighty years, leaving the Arkenstone behind. However, the Dwarves of the Grey Mountains began experiencing attacks by the dragons that still lived in those mountains, and became embroiled in a costly war against them, forcing the Dwarves to abandon the Grey Mountains in T.A. 2590.

The Dwarves went their separate ways with Grór and his followers settling in the Iron Hills and Thrór and his followers settling in the Lonely Mountain.

Under Siege
Under Thror's rule, Erebor was expanded and became “the greatest kingdom in Middle Earth.” The nearby cities of Dale and Esgaroth prospered from its neighboring on Thror's realm, and all other Dwarf mansions were subjected to Thror as the heir to the Throne of Durin.

However, the kingdom's partnerships began to deter, especially since Thror, hoarding a treasure that was beyond measure or any practical use, becoming enamored with the gold and refuse to give Thranduil the Gems of Lasgalen, not heating his old friends warnings that the wealth would bring him nothing but evil. This came to be when the hoard of gold attracted Smaug to the mountain, and resulted in the Sack of Erebor. While Smaug burned the nearby city of Dale, Thorin and his father heroically mustered the Dwarven army at the gate. He was no match for Smaug, however, who trampled his troops. Thorin was however able to rescue his grandfather, who foolishly took the Arkenstone with him to hide in the hoard, not knowing Smaug was already there.

Thorin led an exodus of whatever survivors he could find (not knowing more were trapped in the western guard-room), including his grandfather, and his father, who he heaved. During the exodus, Thorin called upon Thranduil (who came up Smaug's trail with an army) for help. Resentful and unwilling to risk the lives of his kin, the Elf refused. This deed, along with Thranduil's later refusal to house the refugees, would instill in Thorin a deep resentment for all Elves.

Settlement in the Blue Mountains
Throughout most of their journey, the Dwarves settled in human settlements, essentially becoming nomads. After suffering the battles of Moria, and the loss of his grandfather and brother, and the disappearance of his father, Thorin led his people to the Blue Mountains, where they finally established a new colony. While most of the dwarves accepted the Blue Mountains as their home and rebuilt their own lives, especially since Thorin's sister, Dís, gave birth to two sons, Fíli and Kíli, several still saw the Lonely Mountain as their one true home.

In T.A. 2940, Thorin heard that his father had been seen in the wilds near Dunland. Clinging to false hopes, Thorin went looking, in vain. Unbeknowst to him, Azog (who survived) learned of his approach, and sent word through the wild, demanding Thorin's head. Gandalf intercepted such a message and showed it to Thorin on his way back through Bree.

Gandalf, who saw the message as a sign of rising evil, tried to convince Thorin to undertake a quest to reclaim Erebor. Thorin, reluctant to take on the quest, and not entirely trusting Gandalf, informed the wizard that he requires The Arkenstone to exert his authority over the other Dwarf Lords and marshal an army against Smaug. Gandalf offered to call upon a burglar to help sneak it past the dragon. Thorin called upon his people, and twelve of his kinsmen answered. Gandalf bade them to the burglar's home, which he marked. Meanwhile, Thorin sent a call for emissaries from all seven Dwarf kingdoms to come to his halls, asking their aid in the Quest of Erebor, which he was denied. Thorin was taken aback by Gandalf's suggestion to use a Hobbit as the burglar, but nonetheless agreed to meet him.However, Thorin's attempts were unsuccessful and instead, settled with the other twelve dwarves who answered his call.

The Quest of Erebor
In T.A. 2941, Bilbo Baggins and Thorin's company traveled to the Lonely Mountain to regain the treasure Smaug had stolen. Set into the side of the mountain was a secret door, five feet high and wide enough for three to walk through abreast. Gandalf had managed to obtain the door's key, which fit a key hole which could be found only when the setting sun and the last moon of autumn (also known as Durin's Day) were in the sky would the light shine upon the keyhole. Bilbo entered the mountain himself, stumbling upon the dragon Smaug, who he met for the first time. The company tried to eliminate Smaug themselves by burying him under molten gold made in the forges; however, the trap failed.

Smaug was enraged by the actions of Thorin and Company and, to punish them, set his eyes on destroying Lake-town and its citizens. When Smaug came to the city, the Master packed up his treasure and left by boat.

He was however crushed under Smaug's carcass when Bard slew him, but not before the dragon conflagerated the whole of the town and many of its people.

Battle of Five Armies
The survivors fled by boat to the shore, where they lived in tents before Bard came and ordered them to leave for the ruins of Dale. Thranduil came to his aid, but only with the intention of recruiting the people of Laketown to his cause of forcing Thorin to surrender some of the riches of the mountain to him. Bard convinced Thranduil he could reason with Thorin without the need to go to war. However, Thorin, overcome by the gold sickness, refused, sending Bard away. Without any other option, Bard and Thranduil joined forces, leading to a small siege around Erebor. During the night, they were visited by Bilbo, who Bard recognized from Lake-town, who gave them the Arkenstone, believing that they could use it to thier own advantage.

Meeting at the front gate, Thranduil and Bard ransomed the Arkenstone; however, Thorin did not believe it was the stone he was searching for until Bilbo revealed it was the true Arkenstone, revealing the truth. Enraged, Thorin nearly killed the hobbit, believing it was betrayal until Gandalf intervened, demanding Thorin release Bilbo and remarking that he was not making a splended figure as King under the Mountain. The dwarf king released Bilbo but banished him from Erebor, refusing to ever accept help from Wizards or Hobbits ever again.

Dain Ironfoot arrived at that moment, and a small skirmish ensued among the Dwarves, Men and Elves. Gandalf attempted to reason with Dain, telling them they were all fighting the wrong enemy and the true one was heading its way, led by Azog, who was sent to take Erebor for his master, Sauron because of its' strategic position. However, the elves and men began to fight the dwarves, who appeared to have the upper hand until three Were-worms dug through the ground, as the Forces of Dol Guldur emerged. To Dáin, Thranduil and Bard's horror, Gandalf had spoke the truth upon watching Azog's armies emerge.

The three Free Peoples almost did battle with one another, but then Orcs attacked and the Dwarves, Elves, and Men joined ranks together with the eagles against the Orcs, in what became known as the Battle of the Five Armies. The battle extended to the city of Dale, meant to serve as a distraction. As Dáin and his people fought, they were lost without Thorin's absence.

After Thorin overcame his gold sickness, the Dwarves emerged from the mountain, the company joined in the Battle of the Five Armies. Thorin decided to lead an assault towards Azog's command tower in Ravenhill. Dwalin, Balin, Fili and Kili commandeered a Dwarven war chariot, following Thorin through the frozen channel of the River Running. Azog, intending the entire battle as a trap for Thorin, tried to stop his friends from reaching him, sending ogres, a Troll and Wargs after them. Bofur, astride a Troll, managed to help them against the Troll, but the Wargs forced Dwalin, Fili and Kili to take the mounts and leave Balin behind to fend off his foes while they went to Ravenhill.

During the showdown between Azog and Thorin, the Eagles, Radagast and Beorn arrived, quickly dispatching the Gundabad army. During the battle, both Thorin and Azog mortally wounded each other, resulting in their deaths.

Aftermath
In the wake of the battle, a funeral was held for Thorin Oakenshield, Fíli and Kíli, with members of Thorin and Company, Beorn and Radagast in attendance while those in the city of Dale honored those who had fallen in Battle. The mountain was garrisoned by the Dwarves of the Iron Hills and portions of its wealth were distributed to various parties like the Men of the Lake, who set up permanent residence in Dale and elected Bard as the new Lord of Dale.

The Elves of Mirkwood stayed just a short time to receive their share of the treasure before returning to their forest homeland. With Thorin and his immediate family members dead, Dain succeeded him as King under the Mountain. His job done, Bilbo Baggins parted ways with the Company and returned home to the Shire with Gandalf with his secret magic ring always close at hand.

Repopulated with Dwarvish colonists from each of the seven Dwarf kingdoms, Erebor was soon restored to its former glory and flourished once more, as did its neighbor-city Dale. In time, Erebor retook its place as the most powerful Dwarf kingdom in Middle-earth.

Prelude
In the years following the Battle of the Five Armies, Sauron rose to power yet again and sent his evil minions across the entire country of Middle-earth. He sent the Nazgûl to the Lonely Mountain, demanding to know where Bilbo Baggins and the ring were. Sauron offered an alliance with the dwarves, but Dáin refused and decided to warn Bilbo of the threat looming over him. He sent Glóin, Gimli and several other dwarves to Rivendell to attend the council of Elrond, where it was discovered that the ring Bilbo found was the One Ring Sauron was looking for. While he and Saruman spent their time fighting both Gondor and Rohan, he sent the Easterlings to deal with the dwarves of Erebor and the Men of Dale

Battle of Dale
The demise of Smaug was not to be the last of Lonely Mountain's many troubles. In T.A. 3019 on the 17th of March, a horde of Easterling soldiers from Rhûn swarmed over the Redwater river, opening up a second front in the northern theater of the War of the Ring. The sheer force of the feared and renowned Easterlings crushed the Men of Dale and routed their forces, which had to rally back to the protection of the Lonely Mountain.

The Dwarves and Men fought a pitched battle against the invaders, in which King Dain and the king of Dale at the time were killed, eventually emerging victorious over their opponents. The impenetrable gates and walls of the Lonely Mountain, furnished and extensively worked with advanced, complex and intricate Dwarven stonework, defense planning and smith-work, easily withstood the siege equipment of the Easterlings. The Lonely Mountain itself was a key strong-point and gave its defenders great tactical leverage against the attackers, being able to shoot arrows and fling stones down below in reprisal. The many years invested in improving the Lonely Mountain's defenses had paid off, and the defenders outlasted the Easterlings in the siege. The Easterlings then withdrew, suffering disproportionate casualties because of their botched campaign and their difficulty in combating the Dwarven technology, weapons, armor and defenses.

Fourth Age
The Lonely Mountain was a minor place for battle during the War of the Ring. The city took a small hit but it was rebuilt during the Fourth Age with the help of men and all of the Dwarves. With the restoration of the Kingdom under the Mountain the area became prosperous again. Dwarves and Men reforged their friendship. Dáin was killed during the War of the Ring, and was succeeded by his son Thorin III Stonehelm who ruled well into the Fourth Age.

During this time, Dwarves from the Lonely Mountain helped rebuild cities in Gondor and the fortress of Helm's Deep.

Some went to the newly established Dwarven realm of the Glittering Caves where Gimli was lord. However, Gimli would eventually leave for the Gray Havens with his best friend, the Elven prince, Legolas. Late in the Fourth Age the Lonely Mountain was attacked by a large force of Orcs which was destroyed easily by the Dwarves. After this it is thought that the Lonely Mountain continued to flourish for many years after.

Military
Erebor had a strong well armored and equipped Dwarven army able to defeat even the toughest foes. The Army consisted of over 10,000 Dwarves of Erebor.. They had only Infantry, Artillery Machinery and Mounted Machinery as Balin stated while riding a war chariot " It's been a while since I rode on one of these things". Possibly the strongest Artillery in Middle-Earth as it is stated that a huge army of Easterlings tried to attack Erebor/Dale in the TA "but they were no match for Dwarven Machinery,weapons,armor,and defenses."

If counting all Dwarven forces the number would rise significantly as it is stated in the trilogy that the "Dwarves will defend their kin no matter what"