"Minerva. A very clear character with some bizarre inconsistencies under the surface. Deceptively easy, in light of FE11. Rather difficult in light of FE3. Maybe fans, including me, want her to be “stronger” than she is and just flat-out don’t appreciate what the character actually is."
I think that might be true, in a way, but not because I fangirl Minerva; more, it's that the script sets me up with a pivotal moment for her - such as there are in spare stories like FE1/11 - that implies she IS a strong, compassionate, honorable, and maybe driven character, and with that moment in mind, the complete 180 she does later is jarring and seemingly OOC. But when I looked again at her conversations in FE11, I realized the seeds of that final decision are there, and I just didn't realize it because FE11's rewriting of FE1's characterization really does obscure the original intent-- in a good way, I think, but not in a way that's consistent with the apparent end goal for the characters.
Take this conversation she has with Marth right before your final attack on Macedon:
Marth: Princess Minerva, we will soon reach the Macedonian border. Are you certain you wish to join the battle? If you've any reservations about fighting your own countrymen-
Minerva: If I did, Prince Marth, I would not have offered you my axe.
Marth: But surely-
Minerva: You have the wrong idea. Perhaps you think I wish to spare my brother and former vassals, forgive them for seeing things differently?
Marth: ...Don't you?
Minerva: I would be lying if I said I did not wish it were that simple. But history needs to remember that when Macedon went astray, it was a Macedonian who set things right.
Marth: Even if it means your own brother may die?
Minerva: Since I was little, I followed in Michalis's footsteps. Whatever books he read, I read; whenever he practiced the sword, I was close by, watching, learning...He was always a step ahead: my hero, something to aspire to. Even now, some part of me loves him. ...I love him enough to spare him death on some stranger's sword, you see? Let him be punished by my hands.
Then you have her conversation with Michalis when she attacks him:
Michalis: Well? Strike! A moment’s hesitation spells death on the battlefield. I know I taught you better.'
Minerva: … You will not lay down your lance and walk the right path?
Michalis: Don’t be a child. There are no right paths; just mine and yours, two that will never cross.
Minerva: Very well. Then you leave me no choice. Embrace you I shall, Brother!
They say what makes a character is her/his decisions. This decision would say she has some steely inner strength.
Though Michalis refers to hesitation, there isn't really; Minerva hasn't shied away from confronting her brother for his tyranny, from doing what's right. And if she doesn't want to attack her own brother, and hesitates-- well, Michalis is also hesitating. Why else would say this to her? He's both scolding her as a teacher and elder brother might, and trying to absolve her of guilt over the confrontation, or so I read it. My fangirl love of Michalis might be warping my interpretation a bit. :p Certainly, I have tons of thoughts on him that I'm making myself not say here, because they aren't the point.
So Minerva kills her brother (or thinks she does), regrets it, but takes the crown of Macedon after the war and tries to rebuild in a way that suits her morals. We don't know much about this time, except that apparently she pissed off a lot of the old generals; I think she went too soft on them, because she was more idealistic on this one point - what a good ruler should do, what a good country might be - to take the steps her brother would have, and nip rebellion in the bud. Possibly she thought to run it in a military-minded way; possibly she subscribed to some of Marth's idealism. Either way, she didn't crack down on the people she needed to, so they rebelled and imprisoned her.
There's implication this rebellion happened because of Hardin's interference, and that maybe they might not have been as successful without that, but the fringe elements were there to begin with. A miscalculation on her part, which I think she takes very hard.
I've thought for a while that might've been the turning point. It's obvious. Who the hell knows how she was abused, verbally or physically, and with her seeming failure to rule hanging over her head? By now we realize Maria has also disappeared, and the script makes very clear how much she loves her siblings. Minerva's defection to your side in the first game depends on saving Maria. She clearly has rebellious tendencies even before, but she won't step out of line until she knows her sister won't be hurt. And that's normal enough, really. There's nothing in FE11 to imply Minerva loves her family any more fanatically than the next person...
... except that she clearly idolizes Michalis, and seems to follow in his footsteps exactly. It's interesting how her final ending reflects his, only without the dying. More on that later, if I remember.
I think until now I underestimated how much of a blow that rebellion was to Minerva's pride. Or, if not pride, then confidence. Maybe she never thought of herself as monarch material, but I do think she was confident in her ability to lead the military, and it seems to me that the only people hanging around Macedon who aren't military are the commoners, and they all seem to love her. It's the rebellion of the military, not the failure of her rule necessarily, that strikes her to the core and makes her doubt her ability to lead the country. And maybe this doubt, coupled with Maria's questionable condition after being used by Gharnef, might be enough to make Minerva ditch the throne - because Marth is supposed to rule the place anyway - and devote herself to taking care of her sister. Not only that, but leaving, whether she goes to a convent or not, doesn't preclude helping her people. If that's all she desires to do, if saving Macedon and making it peaceful is all she wants, she doesn't need to sit on the throne. Her reputation and connections would be enough to help her along in doing something about that on a private scale, maybe. So: I no longer think it's out of character for Minerva to give up the throne. I think on closer examination her character reveals a tendency to value her family above politics, and Maria probably needs her love and care.
I'm assuming that being used as a vessel to revive a dragon would be kind of traumatizing for Maria.
FE12 kind of cements this opinion. Her supports with the pegasus sisters, going by Hitomi's rough translations, indicate Minerva has indeed decided that she isn't a competent ruler (Minerva--Palla #3), or rather, that she doesn't believe she has the strength or skill to bring Macedon out of ruin:
Minerva: For some time now, I have been mulling this over constantly. Was that truly the best choice, I wondered? I have never been able to rule as skillfully as I wield a spear. I've been contemplating how I ought to deal with that inability of mine. As such, my duty became clear. Any moment now the war will reach its end; should I not then step aside? [loose because it's one long, complicated sentence @_@]
Palla: Do you mean that -- you intend to forsake the kingdom?
Minerva [this is all seriously loose]: Forsake? I love Macedonia. If I were able to, there is nothing I would do not do [for the country]. However... I believe that for a new future, there must be new blood. In order to truly revive that beautiful homeland of ours, a fresh breeze must blow as well. For that sake, we of the old blood of the royal family must therefore be condemned.
Pegasus Knight doesn't seem to have their conversations up yet, so I can't do my own translation... which would be even rougher anyway, so. :D; It's easy to forget that Minerva has no training in running a kingdom. She seems so sure of herself in FE11, (and isn't vastly different in FE1/3 except that she doesn't have that conversation with Marth up at the top of the post), but Michalis was always the heir apparent; Michalis was trained to rule, and Minerva was trained to fight, and only inherited the crown by accident. By her own words, she followed him and did everything he did, all her life. Her support with Catria (#2) reveals that she started out as a pegasus knight and gave it up for a dragon because she thought it would give her the appearance of strength - not to mention Michalis, dear big brother, is a dragon knight.
But is that what she wanted? That's left ambiguous. And during the first war, was she looking to rule, or simply set things right? She probably had no idea how to approach it, and took the role because there was nobody else. Archanea-verse doesn't seem to like letting women sit on thrones, so it's not out of the question to think that any training Minerva got in government would've been second-hand from her brother, and we all know how his first rule turned out.
His return in FE12 makes Minerva's ridiculous ending a little less unreal. In their support conversation, she's of the opinion that her desire for peace and Michalis's desire to make Macedon strong are not incompatible, but Michalis thinks the idea of working together is unrealistic and challenges her to oppose him again if she wants to make her dream a reality.
Instead, she withdraws. I don't have a translation handy, but I recall hearing that Minerva's ending is basically the same, only it doesn't involve a convent or orphanage anymore. In light of Michalis's survival, her withdrawal has a different flavor: now she's choosing either to avoid fighting him again, or simply removing herself from the stage so there's no conflict over his return. Either would be well enough in-character after all the information these support conversations give us. She steps aside in favor of the brother she loves, and (possibly?) decides to take care of Maria, instead. Or, do something else to help Macedon.
All said, even though FE12 is generally accepted as a cracktastic and awful interpretation of the original story, Minerva seems to be represented straightforwardly. If anything, this makes her choice at the end explainable, where before it came out of nowhere and seemed completely out of place. Minerva as she stands in FE11 seems like a strong character capable of grabbing Macedon by the scruff and shaking it until it obeys, and she didn't have enough dialogue in FE3 (in my opinion) to support the sudden change. By itself, her ending looked like an excuse by the designers to allow Marth to rule everything. But now, with her insecurities laid out clearly in her supports, her decision makes a lot more sense. If Michalis lives, leaving does save Macedon from more conflict, and she did just tell Palla that she'd do anything to save her country. 'Anything' apparently includes letting her brother pick up where he left off, regardless of her opinion on his ambitions. Her idolization of him explains the rest.
This might be a bit disappointing when she sounded like such a badass in FE11, but Michalis staying alive, however unwise and silly that seems when you think of storyline integrity, actually saves Minerva's character for me. I can at least imagine practical reasons she might choose to give up the throne, when in the other scenario there's nobody around to take up the reigns after her.