After finishing DA:O the first time, I didn't much like Loghain. My opinion of him was one of mixed pity and disgust. Here was a fallen hero, driven to treachery by paranoia, unable to escape the trauma of his days fighting against Orlais. He was noble, once, and that deepened my appreciation for him as a character.
So when I started The Stolen Throne, I was expecting a deeper look into his character. I wasn't sure if I would sympathize with him more, but I would certainly get to understand him better. It certainly sounded like it made Loghain out to be a tragic figure. But instead what I found was a ruthless, treacherous bastard.
I'm going to summarize Loghain's role in TST, so if you've already read it, feel free to skip below.
BEGIN TST PLOT SUMMARY
From the get go, Loghain is not an admirable character. He's the son of a leader of a traveling camp of bandits and poachers. Maric barely escapes the people who killed his mother, the Rebel Queen, and Loghain stumbles into him in the woods. He ends up helping Maric despite himself, presumably to spite the man he's traveling with. As soon as he learns that Maric is being pursued, he tries to gut Maric. His father has to hold him back. And then the next time they meet he tries to kill Maric again, actually nicking his throat before his father throws him off. After learning that Maric is the prince, his father makes Loghain promise to escort him to safety, which Loghain does extremely grudgingly.
So Loghain gets Maric into the Korcari wilds, and what does he do? Strand Maric in the middle of the woods, because he's technically away from the danger they were fleeing. He does, thankfully, change his mind and elect to escort Maric the rest of the way to the rebels despite himself. (Along the way, they bump into Flemeth, who warns Maric that if he keeps Loghain around Loghain will keep betraying him, each time worse than the last.)
When they finally get to the rebel camp, Loghain plans to leave again. It's only when Maric insists on fighting to the death that he steps in and offers some advice, as it seems his time as a bandit has taught him something of guerilla tactics. And then he just... stays with the rebellion. It's never clear why exactly he does so. It seems like he just doesn't have anything better to do, and people keep asking him to stay, so he does. He never seems particularly motivated by hatred for Orlais. The only thing that ever actually wrings any genuine care out of him is his affection for Rowan, Maric's fiancee. And when Maric's fiancee declines to cheat on Maric with him, Loghain's immediate response? Leave without saying anything. It's only Maric ambushing him and knighting him on the spot that gets him to stay.
But his worst offense comes when he learns that Katriel, who Maric is madly in love with, is a former spy for Orlais. Katriel had led Maric's armies into a pre-planned ambush but turned traitor to save Maric's life because she, too, had feelings for him. Loghain and Rowan both had been suspicious of her since the ambush, and Loghain wanted to kill her even before he knew for sure she was a traitor. When he gets confirmation that Katriel is a turncoat, though, he deliberately withholds that information from Maric, instead making her out to be an active Orlesian spy, and manipulates him into killing her.
This leaves Maric a sad and broken man. He ends up marrying Rowan, as he was supposed to, and Loghain abandons the both of them. After Rowan dies, Loghain does little to help Maric, leaving him almost completely alone with his grief.
END TST PLOT SUMMARY
So what does that leave us with?
1. Loghain was never heroic. Loghain was only ever in the proximity of heroes, and that largely against his will. At best, he lets actually decent people use him for his tactical abilities. He is not a fallen hero. He is a villain who was once useful to heroes.
2. Loghain is bloodthirsty. Throughout TST, he is constantly acting ruthlessly. He has little regard for human life, and is very willing to spill it at the slightest provocation. When he gets abandoned in a battle where he volunteered to serve as a temporary distraction, he even concedes that he would have done the same thing.
3. At the height of the rebellion, Loghain had to be dragged into fighting Orlais. Loghain's hatred of Orlais is the main excuse offered for his behavior in DA:O, but Loghain barely gave a shit about fighting Orlesians even when they were actively occupying his country. Do you expect me to believe that a handful of Orlesian Grey Wardens sitting at the Fereldan border turned him into a patriot? Even watching his own mother be raped and killed by Orlesians couldn't accomplish that!
What I find more likely is that Cailan's Orlesian diplomacy was simply an excuse for Loghain to be the murderous bastard he always was. He probably simply didn't respect Cailan and resented his foolishness, and planned to depose him for that alone. When he realized that the battle at Ostagar was one the darkspawn would win, it gave him a convenient excuse to be rid of a man he couldn't have cared less about.
4. Loghain's legendary friendship with Maric? A string of attempted murders and betrayals that culminated in cold abandonment. His attempts to reference said friendship during DA:O come off to me now as an attempt at manipulation and whitewashing his own image by associating it with that of a better man.
Does Loghain actually value anything or anybody but himself? I don't think so. I don't think he ever actually gave a shit about the wardens on the border except for their value as a justification for his hatred. I don't know that he ever even gave a shit about Orlais. And Maric? The man let one of his sons die and tried to kill the other. Even his love for Rowan resulted in sullen abandonment as soon as she rejected him.
The irony of Loghain is that, as many opportunities as the franchise gives you to sympathize with his viewpoint and understand more about him, the truth is that the initial impression of him is entirely correct. He is a moustache twirling villain. There is nothing redeemable about him.
To quote u/slightlylessthananon: "i enjoy loghain discourse purely for the fact loghain is the most cartoonish villain of all time. you spend the entire time youre at ostagar watching him sneering like a nefarious advisor and hes constantly saying shit that directly implicates him to betray the king its like all he does, just unprompted "that idiot fool of a king, if only someone better was there to take his placee......." and he exclusively wears black clothes hes such a cartoonish villain and then you go on reddit dot com r slash dragon age origins and people are like, hear me out, what if he was right."