The Western Kingdoms, or the lands of Westmarch, Khanduras and Entsteig, are regions in the Diablo world. Some of these kingdoms are central to the games’ storylines, as Diablo and Act I of Diablo II are set in Khanduras, but others appear to have been added merely as flavor.
The Western Kingdoms
The following text from the game manual describes the three kingdoms in general terms:
"Sandwiched between the Barbarian lands to the north and the vast deserts to the East lie the mountainous, verdant forestlands of the Western Kingdoms. The Western Kingdoms are comprised of the three regions: Entsteig, Khanduras, and Westmarch. The smaller, self-contained kingdoms contained herein have developed unique rules of protocol and etiquette, leading many to consider the Western Kingdoms as the most civilized of lands. Such exalted opinions stand in surprising contrast to the youthful age of the realm. While long a destination of merchants and peaceful travelers, recently infighting has made the Western Kingdoms a common destination for mercenaries and other, more sordid, visitors.
The Western Kingdoms are well known for their rich woodlands, a result of the area's nutrient laden soil, pleasant rainfall, and mild climate. From the massive pine and spruce, to the supple yew and ash, these woodlands are unequaled anywhere in Sanctuary. These abundant, fine-grained woods are forested for housing, farming tools, and weapons of warfare. The Sisters of the Sightless Eye, who make their homes within the provinces of Entsteig, are renowned for the bows that they fashion from these trees.
But as the shadows fall across all of Sanctuary, the Western Kingdoms too, are changing. The once familiar creatures that have inhabited these forests have become warped, aggressive versions of their natural forms. Woodsmen have spotted several of the following creatures, and have submitted their reports so that travelers and heroes alike may be better prepared to encounter these foul beasts."
Khanduras is central to the Diablo storyline, as its capital, Tristram, is home to the monastery constructed by the Horadrim to contain Diablo’s Soulstone. The events of Diablo take place in Tristram and in the depths beneath the town, with the player searching for the cause of the region’s corruption and ultimately battling Diablo himself.
In Diablo II, Khanduras is without any central authority and overrun by demons and corrupted beasts. Act I takes place in Khanduras, with the player tasked by the Sisters of the Sightless Eye to retake the Rogue Monastery and clear the pass to the East in pursuit of the Dark Wanderer.
Although it does not appear in any way within the game itself, Westmarch is briefly mentioned in the Diablo manual, where it is described as "the great Northern kingdom" and a land ruled by fervent believers in Zakarum. Westmarch is a strong ally of Khanduras prior to the game’s storyline, though immediately prior to the game's beginning, Westmarch was unsuccessfully invaded by the armies of Khanduras at the command of the maddened King Leoric.
Westmarch plays essentially no role in Diablo II. However, it is worth noting that the map of Sanctuary in the Diablo II manual directly contradicts previous information on Westmarch from Diablo, as Westmarch appears west and slightly south of Khanduras, whereas the Diablo manual describes it as a “Northern kingdom.” The Diablo II geographic placement is usually assumed to be the correct one, due to its later release date and greater detail of Sanctuary. Its capital is Duncraig.
Entsteig is not mentioned at all within either Diablo or Diablo II, and it has no major cities shown on the map of Sanctuary in the Diablo II manual. It is to the north of Khanduras, between the Western Kingdoms and the Barbarian Highlands.