The tragic tale of King Leoric's fall is told in the [http://diablo2.diablowiki.net/[Diablo_I_Manual#Book_II_-_The_Return_of_Terror THE_RETURN_OF_TERROR|Diablo I manual], and through the quests and books of lore found in the dungeons in that game.

Leoric was the ruler of [[Khanduras]] and was a just and wise king. He established his castle in the town of Tristram, near the ancient and decayed [[Tristram Cathedral|Horadric Monastery]]. Deep within the monastery laid the [[soulstone ]] containing [[Diablo]]'s essence, and though trapped within the stone, Diablo was strong enough to send forth his spirit. The Lord of Terror invaded Leoric's dreams, attempting to corrupt and possess the King. Leoric was able to resist Diablo's presence, but he was driven mad by the ordeal.

Diablo had already drawn in [[Lazarus|Archbishop Lazarus]], Leoric's most trusted adviser, and with Lazarus whispering into his ear, the mad king turned on his own people, executing those who disobeyed him, ordering his army into a suicidal waragainst the friendly neighbouring kingdom of [[Westmarch]], and finally purging most of the townspeople from [[Tristram]] when his son, [[Prince Albrecth]], vanished. (The horrible truth was that it was Lazarus had himself who kidnapped the boy.)