Erebor was built by the dwarves in the middle earth of Tolkien. Over time, Erebor became the richest place in the region. But Smaug, a dragon, invaded Erebor. The dwarves tried to take Erebor back for a long time and failed. Later, Thorin was able to conquer Erebor. And Erebor began to strengthen in this way again. During the ring wars, Erebor was besieged by Sauron's army of Easterners. After Sauron was destroyed, this army disintegrated. And he was allied with the ruler of Erebor, Aragorn. And so Erebor has regained its old strong times.
