Looking at the description of the chaotic alignment in ACKS, it seems to be framed in the same way as the evil alignment in many iterations of D&D, i.e. it is unplayable in most normal groups.
What are everyone’s opinions on this? Is an ACKS-chaotic character viable in a normal, more-or-less neutral-to-lawful group? Can a “chaotic” character be “good” (at least in the context of ACKS’s morality)?
I understand “every campaign is a law unto itself”, but what is everyone’s opinion?
I personally don’t allow PCs to be Chaotic in my game, yet. I feel it’s important to get the players grounded in the setting and getting us all used to the ‘party working together to survive’ ethic before I open it up to Chaos.
That said, I randomly determine the alignment of their NPC hirelings - some of whom have been Chaotic. Their alignment is redacted from the character sheets the PCs have access to. When it comes to what effect their alignment has in play, the Chaotic characters are much more likely to betray, screw over or otherwise mess about with the party.
Chaotic is playable when the entire group is Neutral and Chaotic.
Imagine the game as a World War II wargame. Lawful characters are the Allies. Chaotic characters the Axis. Neutral characters are mercenaries and businessmen dealing with either side.
We can recognize that the Axis was the agressor; that it wanted to destroy freedom and liberty; that, via the Gestapo and the SA, it ruled through force and fear; that it engaged in genocide; etc. At the same time, you could have a Rommel-type who was a fairly decent fellow. There's no reason a group of panzer grenadiers under Rommel couldn't have been Chaotic PCs. You're existentially evil, but you're not personally evil. (Note that Rommel did, at the end of his life, agonize over the rightness of his side, etc. Or see the Saturday Night Live skit: "Are we the bad guys?") You can easily mix in Neutral PCs.
On the other hand, what doesn't work well is trying to have Lawful and Chaotic PCs together. If you imagine the classic module B2, the Lawful characters are trying to clean up the caves, the Chaotic characters are trying to raid the Keep.
Arguably Communist Russia was also Chaotic so I suppose you could find a way to mix-em-up if you have a VeryChaotic power fighting a Lawful and LessChaoticButReallyDesperate power. That would be interesting because once the players get to the higher levels and start to beat off the primary threats, the game will turn into a player-versus-player competition to seize more lands and prepare for the next war.
Actually, that sounds awesome.
On the history note: The Allies weren’t completely free of poor conduct. In WWII the U.S. had internment camps for the Japanese. The Allies carpet bombed (and nuked) civilian targets too. Now if we look into the U.S.'s past, we will see a near-genocide of Native peoples for their land.
What alignment would you brand a character who, while motivated by loyalty and a desire to protect others, still finds certain chaotic practices (like necromancy) are the best tools for achieving his aims? An anti-hero ruler who would tear open the gates of hell in order to protect his people, perhaps? Is it lawful or chaotic to use undead* labor to expand and protect civilization? (*Corpses used are obtained via voluntary donation, executed criminals, and, in the case of the few (if any) intelligent undead, volunteer.) This last one is motivated because, under necromancy, it is noted that a “CHAOTIC” caster of 11th level or higher can perform necromancy, implying that a lawful or neutral caster could not.
A ruler might be a scourge to his enemies, but followed by his people, less out of fear of him, but because he is REALLY GOOD at protecting them from monsters and invaders. “Last Tuesday a group of ogres tried to raid the city’s. They were stopped at the walls. Now we have a patrol of zombie ogres. I for one feel safer with the monsters on our side, especially since they are mostly kept outside the walls and are well looked after.” I’m guessing this qualifies as neutral since it sits between law and chaos, but I’m not sure.
I think the idea is that most things are neutral, and that Law and Chaos are the extremes.
Also, with Law and Chaos as “alignments” rather than philosophies, Lawful rulers can do whatever they want to uphold (demi)human civilization and stability Chaotic ones can follow the rules to the ultimate end of toppling that same civilization.
I’m sure a lawful ruler might have no problem using undead to secure his people. He just couldn’t create them himself (because it’s “wrong”). (Like, I would never dream of declawing a cat, but hypocritically, if I’m adopting a cat, it being declawed is a selling point.)
Then again, supporting the use of ruinous powers to secure your kingdom might not be that Lawful after all. Maybe as a last resort, like how a Lawful ruler can totally war against neutral kingdoms, but only if absolutely necessary.
Well, now I’ve confused things, but maybe I’ve said something useful. Good luck. 
I have found that Thomas Aquinas’ Doctrine of Double Effect tends to be the best answer for these sort of complex “means and ends” ethical questions.
http://plato.stanford.edu/entries/double-effect/
Nothing hinders an act from having two effects, one of which is intended and the other is beside the intention. And yet though an act proceed from a good intention, an act may be rendered unlawful if it be out of proportion to the end."
In the Auran Empire setting, undeath is an impurity or taint on the Logos (Natural Law), and undead are creatures whose souls are being denied the rebirth that the Logos would otherwise offer. Undeath is therefore an unlawful act. Creating undead for your army violates rule 1, above - it’s a morally impermissible act.
That leaves the question as to whether the deed makes the ruler Neutral or Chaotic. I’d use rule 4 to adjudge that. Therefore:
So I would conclude that a Lawful ruler, who uses Chaotic undead to protect his kingdom from the predations of Chaotic creatures, becomes Neutral.
APM: “In the Auran Empire setting, undeath is an impurity or taint on the Logos (Natural Law), and undead are creatures whose souls are being denied the rebirth that the Logos would otherwise offer. Undeath is therefore an unlawful act. Creating undead for your army violates rule 1, above - it’s a morally impermissible act.”
So, at least in the Auran Empire setting, being turned into an undead (even a mindless undead, like a zombie/skeleton?) binds the soul, to its form preventing natural rebirth (reincarnation or afterlife) for a departed individual. This makes some more sense. What if the individual wishes to avoid the rebirth of their soul either to extend their current “life”, out of obligation to their people, to atone for the sins of their life through service, or out of pure terror of what judgement might befall their soul (heck, giving a monstrous psychopath the voluntary opportunity to at least temporarily avoid bad-afterlife (i.e. hell) in exchange for service as a mindless skeleton might be more mercy than they deserve). Is it known what a soul experiences when their body is animated as a mindless undead?
Also, is this “taint on the Logos” a philosophical issue, or capable of measurable harm on the world (much like how sinkholes of evil arise in places of death, do high concentrations of undead create dangerous situations?)
Lastly, what happens when a caster controlling many mindless undead dies? Do they follow their last order until destroyed (making their danger based on just what that last order was) or do they suddenly (or at least eventually) break free and start killing people? What happens when the mage is brought back, or “dies” only to immediately rise as a lich at the end of a successful necromancy attempt?
What if the individual wishes to avoid the rebirth of their soul either to extend their current "life", out of obligation to their people, to atone for the sins of their life through service, or out of pure terror of what judgement might befall their soul (heck, giving a monstrous psychopath the voluntary opportunity to at least temporarily avoid bad-afterlife (i.e. hell) in exchange for service as a mindless skeleton might be more mercy than they deserve). Is it known what a soul experiences when their body is animated as a mindless undead?
Most individuals who choose to become undead would do so for one of the reasons you've described. Are you asking me what, say, a Priest of Ammonar would say to someone who claimed those motives?
Mindless undead (being mindless) are mostly animated by tainted power that was immanent within the environment. As such it's the most innocuous form of undeath. It's not entirely innocuous however. When a person dies, some of their soul (which is itself a shard of the Logos) remains as residue in the body. This is why the Empyrean faith cremates the dead (to allow everything to pass on). The residue of the soul in the body is also what you're speaking to when you use Speak With Dead, and it's what you are tapping when you use a monster part as a special component.
Also, is this "taint on the Logos" a philosophical issue, or capable of measurable harm on the world (much like how sinkholes of evil arise in places of death, do high concentrations of undead create dangerous situations?)
We're getting pretty deep into metaphysics of the Auran Empire here, but the Logos is immanent within everything. I explain it in the Auran Empire “esoteric cosmology” as follows:
“everything in the Cosmos has a trace of the Logos within it, and living things have a veritable shard of the Logos in them. This shard is called the soul, and carries a measure of divine power. “
A sinkhole of evil results when the Logos immanent within an area is tainted. When a body dies within a sinkhole of evil, the taint can seep in, which is why mindless undead rise from dead bodies in sinkholes of evil.
Do undead and sinkholes of evil create measurable harm on the world? The Empyrean gods teach that the transmigration of the soul is not just right, but necessary for the functioning of the world.
The Chthonic gods teach that the transmigration of the soul is a lie, and that the Empyrean gods actually eat your soul. After all, if you are “reincarnated” why don’t you remember your past lives? Chthonic gods (so they claim) are the only truthful gods, because they tell their followers how to become undead and preserve their ego-self.
Again, from the Auran Empire campaign setting:
“The Empyreans believe that after death, the body must be burned so that the spirit can swiftly travel to the afterlife, where its valor is weighed by Türas. Noble souls might pass to the Empyrean Heaven and dwell in the light. But most souls drink of the waters of sorrow and return again to the realms of man in a new body.
“Chthonic faithful do not believe in this cycle of life, death and rebirth. They believe that upon death, the Empyrean gods consume the soul, and then use it as fuel in the creation of new life. They see reincarnation of the soul the same way we see fungus growing in a corpse – new life, yes, but not the same life. They see, not a choice between undeath and reincarnation, but undeath and oblivion. They thus seek to keep their souls and their bodies intact until the time of the Awakening, lest their singular identity be destroyed by the cycle of death.”
“The Chthonic religions all seem to prophesize a time known as the Awakening, when the gods shall return to the earth and the faithful shall enjoy bodily resurrection. The day of this Awakening is said to be governed by the movements of the stars, which are eternal and unchanging, their truth hidden by the false light of Ammonar’s sun.
Lastly, what happens when a caster controlling many mindless undead dies? Do they follow their last order until destroyed (making their danger based on just what that last order was) or do they suddenly (or at least eventually) break free and start killing people? What happens when the mage is brought back, or "dies" only to immediately rise as a lich at the end of a successful necromancy attempt?
The undead continue to carry out whatever their last order was. A mage who is brought back still has whatever control he had over them.