The Scarlet Crusade is a religious order that started sometime following the events of The Frozen Throne. For a refresher, Sylvanas had just killed Lord Garithos, which led to a disintegration in the forces of the Alliance in the former lands of Lordaeron.
Since their kingdom had just been destroyed by undead and their leader was just killed…the survivors of Lordaeron banded together around the one thing that can hurt undead: The Light. So they formed into a religious order to retake their lands.

Blizzard considers them to be the bad guys, by the way.

I won’t beat around the bush: Blizzard fucked up the writing of the Crusade. Originally, I thought it was bad, but not that bad…I’ve changed my mind. The Scarlet Crusade (particularly via retcons) actually breaks the worldbuilding.

I realized halfway thru writing this that…I’m mostly pointing out the worldbuilding issue instead of describing the canon stuff. I’ll maybe fix it later.

So to elaborate on the context again: the Scarlet Crusade was founded by the remnants of the Kingdom of Lordaeron. The Kingdom of Lordaeron was destroyed by Arthas after the latter joined the Scourge. So the Scourge destroyed the Kingdom, killing thousands of innocents in the process. They then also destroyed the Kingdom of Quel’thalas.
Following this, the survivors scrambled together into the Alliance. The forces in the North were led by Lord Garithos. Garithos ended up alienating the Blood Elves^A) and, realizing his mistake later, he actually changed his mind on non-humans. This ended up biting him back, though after Sylvanas betrays him.
The newly-formed Forsaken (Scourge undead who broke away from the Scourge) decided to stay in Lordaeron and, after killing Garithos, presumably destroyed a big chunk of the Alliance in the former lands of Lordaeron.
After the initial chaos, the remnants of the Alliance in Lordaeron reformed into the Scarlet Crusade. So, keep in mind, at this point most members of the Scarlet Crusade are former Paladins, soldiers and civilians.

Now, what would be the logical continuation of all this context?

Now, pre-retcon, the Scarlet Crusade was…still fanatically devoted to the destruction of the Forsaken. But they didn’t mind other races (though they were suspicious of all outsiders). They also may or may not have been aligned with the Alliance. Also, at some point, the leadership of the Scarlet Crusade was infiltrated by a demon.
Post-retcon,^B) the Scarlet Crusade was explicitly founded by someone possessed by a demon. They actively killed every non-human they saw and leaned hard on their Light identity. That retcon also required another retcon related to the Light, which was stupid.

What’s notable though is that both of these characterizations are still completely reasonable. Of course they’re suspicious of non-humans: their former leader was suspicious of non-humans and when he lowered that suspicion, he was immediately betrayed.
But, the big thing that Blizzard misses about the Scarlet Crusade is that it’s made up of the survivors of Lordaeron. And that seriously changes the equation.

This is where we bring up the other thing, which is what breaks the worldbuilding: the Alliance, for some reason, doesn’t like the Scarlet Crusade. The justification(s) given are “racism” and “fanaticism”. But…let’s think about this from a different angle: why isn’t the rest of the Alliance not racist and fanatical?
Why would I suggest that? Because:

1. The Alliance at this point is led by Stormwind. Stormwind’s capital was destroyed by the Horde, like how Lordaeron’s entire Kingdom was destroyed by Undead.
2. Theramore (the other major Alliance faction) is made up of survivors from Lordaeron, Dalaran and other Alliance kingdoms.
3. The High Elves of Quel’thalas are still around.

Now, considering that, wouldn’t Stormwind sympathize with the survivors of Lordaeron? Wouldn’t the people of Theramore be interested in what their kin (possibly their actual family members) are doing in Lordaeron?
Remember that the Alliance was founded by Lordaeron and they’ve now been destroyed by Undead. And the Undead currently there did rebel against the Scourge, but then they destroyed a chunk of the Alliance in Lordaeron…then joined The Horde and are currently harassing the remnants of the people of Lordaeron.
Remembering that the racism and demon-founding is a retcon…the Scarlet Crusade is an ally of the Alliance by virtue of being remnants of the founders…yet Blizzard is claiming the Alliance abandoned the Scarlet Crusade? That makes literally no sense if we consider all the context. It also makes the Alliance look heartless and downright evil.

Think about it, this is like arguing the Byzantine Empire is in the wrong for fighting back against the Rashidun Caliphate…who had just invaded their lands!

Also keep in mind that the people of Lordaeron had to fight genocidal orcs and trolls (who are now in an alliance with the undead). All of this suggests that the Scarlet Crusade is in the moral right, even though they’re a bit overzealous at times.

But here’s the thing, even the racism could be explained. How? Well, when Lordaeron started falling to the Undead, the High Elves and Dwarves sent little to no help.^C) Then, again, Garithos was killed after he trusted non-humans – the one time he put his guard down.
It makes complete sense that they’d be skeptical of all outsiders afterwards.^D) Though they should have High Elves among their ranks.

Also also! The Undead canonically have a natural hatred of the living and the Scourge and Forsaken both attempted to exterminate all life, so that further justifies the Scarlet Crusade’s fanaticism.

This is where I compile my notes on what I think should have happened with the Scarlet Crusade instead.

I’d preserve the original conception: they started out as good (though fanatical), got corrupted by demons…but! This is where I’d diverge.
The corruption should be noticed and after a few near-crippling defeats, they purge the corruption and go back to being good (though overzealous at times). This can be justified as demonic infiltration.
We’d also keep the requirement that The Light requires you’re good – and, to signal the corruption, the Scarlet Crusade might start losing the ability to use the Light, which would confuse them.

Then you make Sally Whitemane the leader of the reformed Scarlet Crusade (fan service).

I’d also soften their approach towards the Undead. If an undead willingly surrenders and is like “help me pls”, then I’d just have them take them captive. This part would be more difficult to justify, but I don’t think it’s outside the realm of possibility on a limited scale. Though it should definitely be added post-reform.
Post-reform, the Argent Dawn would likely lose legitimacy and get absorbed into the Scarlet Crusade.

The RPG has a few story hooks for Scarlet Crusade players and I think this really shows how uncreative the writers at Blizzard (and White Wolf) were: you’re either evil and you believe in the Scarlet Crusade or you’re good and are rebelling/leaving the Crusade. Where’s the “good and wants to reform the Crusade”?
Keep in mind that as a citizen of the Kingdom of Lordaeron, you would have witnessed the destruction of your home, the deaths of all your loved ones and then you’d see those same loved ones being raised into undeath to kill you and everyone else that’s left. Then you’re abandoned by the rest of the world. Yeah, I think I can understand why the Scarlet Crusade is so popular among the people of Lordaeron.

Obviously, I’d have them eventually win the war. The Forsaken have so much going against them as well.

Apparently, and I need to check this, but the class isn’t effective at fighting Undead. While this could be seen in many ways, the important point I want to make is this: if they aren’t good at fighting the undead, why is the Scarlet Crusade so effective against them?

• Scarlet Crusade
• Was the Scarlet Crusade Right? (yes)
  • According to that video, the Scarlet Crusade was originally where the Argent Dawn came from, which means some…interesting things.