Ragnaros

Background
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 attacked Thunderaan, Prince of Air. Thunderaan was utterly defeated and the Firelord feasted upon his essence, but was unable to consume him entirely. Ragnaros divided what remained between his servants, Baron Geddon and Garr.

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.

Around three hundred years ago the ambitious and ruthless Dark Iron clan initiated a war against their dwarven brethren, the Bronzebeard clan and Wildhammer clan, thinking that they were about to unite against the Dark Irons. During this War of the Three Hammers, the Dark Iron dwarf leader named Thaurissan lay siege to the Bronzebeard's capital city of Ironforge, while his wife Modgud attacked the Wildhammer capital of Grim Batol. Modgud was succesful in her assault upon the Wildhammer dwarves, but Thaurissan proved less succesful. The Bronzebeard dwarves repelled his attack and quickly dispatched aid to the Wildhammer dwarves. In a short time, the Dark Irons' fortunes took a turn for the worse, and they were pushed back to the city of Thaurissan, the Dark Iron dwarven home. 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 God, although he is only affiliated with the Old Gods. The Bronzebeards and Wildhammers, however, remain free.