A quick and dirty guide to the lore of the first Diablo game

In order to understand a game franchise, you have to understand where it started. And one of the first things you may have noticed if you downloaded and played the original Diablo — as it has recently become available — is that the story of these games has been changed from the original release. It’s been expanded, and many of the characters given more backstory and fleshed out. At times it can be hard to figure out exactly what’s going on.

The events of the game are, in a certain way, fairly straightforward. There is an ancient evil awake in Tristram, a small town in the shadow of a grand Cathedral built on what used to be a monastery.

The Greater Evils

When the player arrives in Tristram, the town is on the verge of annihilation. The history of the region is sketched out — Leoric, a newcomer to Khanduras, had come to the region from Kehjistan and declared himself King with the backing of the Zakarum faith. What Leoric didn’t understand was that Lazarus, his trusted advisor and Archbishop of the Zakarum faith, had arranged his ascension to King of an unimportant land with no real importance — and dressed it up as a major opportunity to create a dynasty that would some day rival nations like Westmarch and Kehjistan — just to get to Tristram.

Centuries earlier, the three Greater Evils realized that the Eternal Conflict could not be won. Following the Sin War, where the Angel Inarius and the Demoness Lilith used the Worldstone to create a refuge world named Sanctuary and populated it with the offspring of Angels and Demons who would devolve into Humans, a new possibility had arisen — corrupt the Humans and gain a vast, potentially powerful army of souls with which to flood Heaven and finally win the War. But the peace accord at the end of the Sin War kept both Heaven and Hell away from Sanctuary, and the Greater Evils needed a means around that accord.

Lazarus’ work

They got it in their ambitious Lessers, Asmodan and Belial. The Greaters engineered a war in Hell that they deliberately lost, knowing that the Lesser Evils would banish them from Hell, and using that to slip into Sanctuary where they could begin the process of tainting mortals to form their new army.

And it would have worked, too, if not for that meddling Archangel Tyrael and his cursed Horadrim.

Using secret magics taught them by Tyrael, the Horadric Order created Soulstones and used them to trap the three Greater Evils, although Baal managed to damage the stone that was to imprison him so that Tal Rasha, head of the Horadric Order, would use his own body to imprison Baal.

Each prison was entrusted with a single Demon Lord. Under Kurast, the sacred city of the Zakarum faith, the Soulstone containing Mephisto slowly worked to corrupt the very Zakarum who sought to keep it imprisoned, and Lazarus was one of these. His mission was simple — the ancient Horadrim had concealed Diablo’s Soulstone underneath an ancient monastery and then, over the years, had all but died out.  This left the stone unattended, for there was no one who knew where it was to disturb it.

All part of the plan

No one but Lazarus.

Lazarus engineered everything — the travel of Leoric and his family to claim the throne of Khanduras, a sparsely populated land, under the guise of bringing them to the Light of Zakarum. And slowly, Lazarus sought to use the Royal Family he’d helped appoint to free the Lord of Terror from his ancient prison. King Leoric had been the first choice, but he somehow resisted Diablo’s corruption — the great terror he felt at the attempt broke his sanity, but his will was great enough that Diablo could not seize his body. And so Lazarus, on Diablo’s orders, kidnapped the King’s youngest son Albrecht and blamed his kidnapping on the people of the town.

However, in his madness, King Leoric had ordered a war with Westmarch, their nearby and far more powerful neighbor. Khanduras had stood no chance, and when the King’s lieutenant Lachdanan returned from the war to find Queen Asylla dead, Albercht missing and the King a frothing madman who’d executed the former and sought to reclaim the latter by massacring the people of Tristram, he took action. That action was to strike down Leoric, and had it ended there, all might have been well.

But what Diablo couldn’t control in life he could make use of in death, and Leoric rose from the dead at his own burial and cursed the knights who had slain him.

The madness of Prince Aidan

Lazarus took advantage of all this chaos to convince the people of Tristram to form a mob to save their own loved ones as well as the missing Prince, who was well liked by the people. Duped, he brought them into the depths of the Cathedral where many of them met their end at the hands of the Butcher, a hideous demonic servant of Diablo.

It was in this state that Prince Aidan, the elder son of King Leoric, returned home from the doomed war with Westmarch, alongside companions he’d made in that conflict. These three heroes found the town in shambles and unspeakable horrors beginning to emanate from the Cathedral, and sought to find the missing Albrecht and learn the truth. As they descended into the depths of the Cathedral they found that Diablo had converted it into a pit that led to Hell itself, and after striking down both the Skeleton King that had once been Aidan’s father and Archbishop Lazarus himself, they confronted and struck down Diablo. This led them to discover that the Lord of Terror had been using Albrecht’s body as a host, and that Aidan had slain his own brother.

The game ends with Aidan, holding the Soulstone containing Diablo, deciding to house the demon lord in his own body and driving the Soulstone into his forehead in a move that literally everyone who ever played the game knew was a bad idea and which would lead to the events of Diablo 2.

Why did Aidan even think this would work? Well, perhaps he was driven mad at the sight of his dead brother after all the horrors he witnessed on his way through the Cathedral. Perhaps he simply wasn’t strong willed enough to resist the compulsion, as Diablo had always intended to use Aidan as a host for he was far more fit than his younger brother. Perhaps the game needed a sequel bait ending. Regardless, that’s what Aidan did, and that’s how Diablo ended.