Respect Ragnaros!
The Firelord and his brethren once held sway over the entire world. As a servant of the Old Gods, he fought against the Titans for domination over the planet. The victorious Titans banished him and his brethren to the Elemental Plane - there to remain imprisoned until the end of time.
It was then and there that the brothers turned on each other. For five millennia a battle was fought at the core of this world.
It was during the Elemental Sundering that Ragnaros sought to consume Thunderaan, Prince of Air. Thunderaan fell, utterly defeated. The Firelord feasted upon the essence of Thunderaan, but was unable to consume him entirely.
In the center of a vast lake of fire in the Elemental Plane stands Sulfuron Keep, the home of Ragnaros. Until comparatively recently, he ruled his underground land with a molten iron fist.
Three hundred years ago, the ambitious and ruthless Dark Iron Clan initiated a war against their dwarven brethren, the Bronzebeard Clan and Wildhammer Clan. During this War of the Three Hammers, the Dark Iron Dwarf leader named Thaurissan lay siege to the Wildhammers' capital city of Grim Batol, destroying it. Despite this victory, the united Wildhammers and Bronzebeards were ultimately able to push the Dark Iron dwarves back to Blackrock Mountain. Thaurissan, seeking to summon a supernatural minion that would turn the tide of the war back to his favor, called upon the ancient powers sleeping beneath the world. To Thaurissan's surprise, and ultimately his doom, the creature that emerged was more terrible than any nightmare he could have imagined.
Now, freed by Thaurissan's call, Ragnaros erupted into being once again. Ragnaros' apocalyptic rebirth into Azeroth shattered the Redridge Mountains and created a raging volcano at the center of the devastation. The volcano, known as Blackrock Mountain, was bordered by what is now known as the Searing Gorge, to the north, and the Burning Steppes, to the south. Though Thaurissan was killed by the forces he had unleashed, his surviving Dark Iron Clan brethren were ultimately enslaved by Ragnaros and his elementals. Many Dark Iron dwarves remain within the lower areas of the mountain, especially Blackrock Depths, toiling away at the behest of Ragnaros and the Firelord's lieutenants. They worship Ragnaros, considering him not only a Elemental Lord, but also an Old GodLoC 191,192, although he is only affiliated with the Old Gods. The Bronzebeards and Wildhammers, however, remain free.
Witnessing the horrific devastation and the fires spreading across the southern mountains, the Bronzebeards' King Madoran and Wildhammers' King Khardros halted their armies and hastily turned back towards their kingdoms, unwilling to face the awesome wrath of Ragnaros.
Now he lies at the bottom of that volcano on Azeroth, striving to find a way home, as well as to gather his strength once again so he can burn away Azeroth and take it for his own. Meanwhile, in Sulfuron Keep and elsewhere across the Firelands, his elemental princes battle constantly for dominance.
He and his dwarven minions took control of the Blackrock mountain's volcanic depths and made war on the orcs in the Upper Blackrock Spire, which served as the seat of power for Nefarian the Black Dragon. Ragnaros has uncovered the secret to creating life from stone and plans to build an army of unstoppable golems to aid him in conquering the whole of Blackrock Mountain.