Tarkir

Tarkir is a plane based of Mongolia.

Planeswalkers

This is Sarkhan Vol's place of birth. Wasn't really much of after his... spark ignition and dishonorable discharge. It is also home to Ugin. It was also the place of the Pre-Mending battle between Ugin and Nicol Bolas.

Clans

Some of this information has NOT been confirmed (to my knowledge). But it looks like its true.

Each clan fought primarily against a dragon and its brood. Each clan worships the prominent aspect of their respective dragon enemy. When the Khans of Tarkir set first came out, it seemed like all Takir dragons shared these aspects. Each clan (in Khans of Tarkir) is a wedge. A wedge, in mtg, is a color combination of a color and its 2 enemies. The clans were based around a single color, and one of that color's allies and one of its enemies. In the mana cost of the wedge cards, the color the clan is primarily based around is to the left. The middle color is the enemy of both remaining colors to emphasize in Triple Khans draft (which aren't really being done anymore), its much more flexible to go into 2 enemy colors first instead of 2 allied colors first. The last color is simply the remaining color. The first word of the clans can be used to describe a decks color, regardless of if it actually matches it's clan's theme (E.G. an Abzan deck is any WBG deck). The legendary dragon's that lead the broods are the same color combination as the clan they oppose except they are missing the enemy color. Each clan's

Clans of Tarkir
Abzan Houses Endurance	Jeskai Way Cunning	Sultai Brood Ruthlessness	Mardu Horde Speed	Temur Frontier Savagery

Settings of Magic: The Gathering
Pre-revisionist:	First Magic Sets - First Urza Block - Arabian Nights Legends - Homelands - Ice Age - Mirage
Weatherlight Saga:	Portal Starter Sets - Second Urza Block Tempest Block - Masques Block - Invasion Block
Post-Weatherlight:	Otaria Block - Mirrodin - Kamigawa - Ravnica - Time Spiral
After the Mending:	Lorwyn - Alara - Zendikar - New Phyrexia Innistrad - Return to Ravnica - Theros - Tarkir - Eldraine - Ikoria
Two-Block Paradigm:	Kaladesh - Amonkhet - Ixalan
Post Two-Block Paradigm:	Eldraine - Ikoria - Kaldheim - Strixhaven
Never in a standard set:	Fiora (Where the Conspiracy sets take place) - Kylem (Battlebond)