Rift is a MMORPG set in a fantasy world called Telara, which is the focal point of several different elemental Planes.
These Planes are realities representing the elemental forces of Air, Fire, Water, Earth, Life, and Death, and it is at the one point where every one of these Planes intersect with each other that Telara exists. Each Plane is governed by a Dragon-deity, which is the personification of that elemental force. Through the actions of the Dragon of Extinction, Regulos, the various Dragons have united in an alliance known as the Blood Storm, for the purpose of invading Telara and gaining use of the intersection of all of their realms. In the past, the Blood Storm was defeated by the inhabitants of Telara with the help of the Vigil, the most powerful of the native gods of Telara.
Regulos was cast out into the elemental Planes, while its five compatriots were trapped within Telara and chained beneath a Ward designed to close Telara off from external threats. However, recently, Regulos has gained entry to Telara, destroying the Ward and causing Rifts to open to the elemental Planes, feeding the strength of the trapped Dragons and allowing their minds to enter in a bid to destroy Telara's defenders.
Opposing Regulos within Telara are two factions: the Guardians and the Defiant. The conflict between these two factions serves as another source of tension and gameplay. Players have the role of Ascended, superhuman resurrected warriors whose task is to defeat the forces of Regulos and cleanse Telara forever of the threat of the Storm. The Guardians piously follow the religion of the Vigil, the supreme gods of Telara. They include the high elves, the Mathosians (a warlike culture of humans from the north), and dwarves. Ascended Guardians were resurrected by the Vigil after dying at the hands of Regulos during its return to Telara. Players of Guardians fight and die against one of Regulos' commanders, only to be brought back at the beginning of Rift.
The Defiant are those who, for cultural, historic, or personal reasons, do not follow the religion of the Vigil and have put their trust in science and technology as a way to conquer the forces of Regulos. They include the Eth (a highly advanced human culture from the south), the Bahmi (descendants of interbreeding between Air spirits and humans), and the Kelari (animistic, cabalistic dark elves). Ascended Defiant were resurrected through technology based on the study of the soul-structure of Ascended Guardians in an apocalyptic future in which Telara has nearly been consumed by Regulos. At the beginning of the game, players of Defiant are sent back in time from this point to the beginning of Rift, allowing them to fight at an opportune moment in Telara's timeline, to overthrow the religion of the Vigil and defeat Regulos.