Zephiel married Guinevere.After Desmond announced that Guinevere's husband would become the next king of Bern, there was quite a bit of outrage from those who were loyal to Zephiel, and who had expected Zephiel to become the next king. To placate the people of Bern while still holding true to the letter of Desmond's proclamation, Zephiel and Guinevere got married. This was the last straw for Desmond, who then made his last attempt on Zephiel's life...
The reason Bramimond resurrected Ninian to help deal with the three dragons is because ice is super effective against dragon.
Roy was named after Roland.Or possibly, "Roy" is a nickname and "Roland" is his full name, kind of like "Lyn" was a nickname for "Lyndis."
Karel killed Geitz and Vaida.If you go through Dart and Karel's supports, you will find that Dart tells Karel of a female Wyvern general who is the strongest of the four Bern generals. Vaida was supposedly expected to be killed on her return to Bern because of her betrayal (Heath may have been killed too, as he is able to join her). However, Karel says he will "keep her in mind" and is known to hunt out strong people with reputation (which is why he talks to Dart, who knows the rumors). Vaida and Heath survive the journey and maybe talk to the prince, but Karel was right behind them and killed Vaida. Heath dies trying to protect her. That would explain why they don't appear in 6. Geitz, on the other hand, has a brother named Geese who appears in 6, but Geitz himself is absent. Geitz feared Karel and that fear was what give him the ability to sense when Karel was near. Karel even compliments Geitz's skill, but denies trying to launch a sneak attack on him. Geitz's natural fighter's instinct and his ability to sense Karel's presence finally won Karel's respect and, with that, Geitz was destined to be challenged by Karel. Since Karel appears in 6 and Geitz doesn't, it is possible Geitz was killed in their fight.
The dead friend Renault wanted to bring back is Kishuna.Renault's battle conversation with Nergal in Hector's story suggests that Nergal was still experimenting with morphs when Renault came to him, and Kishuna was Nergal's first morph. Renault also refers to what Nergal gave him as "soulless" and "an empty vessel". Unlike most of Nergal's morphs, Kishuna isn't even capable of speech, which could lend to him giving off this impression. It would be interesting to see if anything unusual would happen if Renault were to be hacked to be able to attack Kishuna in Chapter 32x...
The world behind the Dragon's Gate in FE7 is in fact Archaneia, the continent of FE1/3/11.The Dragon's Gate is on the same spot as the Ice Dragon Temple in FE3. Nils and Ninian also mention how men and dragons live there together, which applies to Archaneia as well.
Wendy's parents are Oswin and SerraThere are no female A-knights in 7, and they're rare in the setting in general, so if it's in Wendy's blood at all, it must be from her father's side. Wendy has crappy DEF and STR for an A-knight (even taking starting at level 1 into account). Of course, you could argue that's just due to being a girl, but it wouldn't make sense for her mom to be someone like, say, Vaida. It's clear she's uncomfortable with the role and that would make sense if her parents were radically different. Finally, she has pink hair, which is unusual even for Fire Emblem. Now, what canon pairing involves a male A-knight and a non-combat-type female with pink hair? Bingo.
Lowen is the cook/meal delivery man in FE6.We know Lowen as the eager-to-please Pheraen cavalier in FE7, in which he spent an entire set of supports lecturing Eliwood on the importance of proper nutrition, as well as revealed that he had been cooking for the army surreptitiously. In FE6, Lugh mentions in his supports with Chad and Ray that the man who delivered meals to them in the field has given him extra baked tarts. Klein also mentions, in his A support with Percival, the cook's concern that Percival doesn't like his meals because he eats them without expression. Neither of these men is given a name, but they both seem to share the same concern over making sure everyone in the army gets enough to eat and, what's more, that their food actually meets their preferences and tastes good (which, from what I've gathered, is unheard of in any military). It's likely that at least one of these guys is actually Lowen returning to (half of) his previous role, if the two unnamed caterers aren't, in fact, the same person.
The Juna Fruit isn't actually exclusive to Magvel.In Sword of Seals, the character Gonzales can be found at level 12 on one route, and level 5 on the other, but his stats are the same regardless. This is consistent with the effects of Juna Fruit. Note that to drop 7 levels, Gonzales would need to have eaten at least two Juna Fruits, as there is a 5-level maximum per fruit. How he managed to get two of what is obviously a very rare delicacy in Elibe is anyone's guess, though the most likely scenario involves the corrupt nobles who push him around, seeing him only as a weapon and therefore thinking only to make him stronger.
Limstella was modeled after Nergal's wife.Before the chapter in which you fight her, Nergal comments on how Limstella was the most powerful of his morphs. However, Limstella is a very plain woman. Other than the black hair and yellow eyes that all morphs come with, she doesn't exactly stand out. Not exactly imposing enough for someone to choose for their champion. This could be a case of Boring, but Practical, but considering that Nergal lost his sanity to the dark powers trying to bring his wife back from the dead, it wouldn't be a far stretch to believe that when making his most powerful morph, that some lingering presence of her in his mind influenced his design.
Harken is the mystery villagerIn one village in FE7, a man who doesn't reveal himself claims that he dresses in the garb of the Black Fang, but is an ally and a loyal citizen of Lycia. All these apply to Harken, who suicidally infiltrated the Black Fang to kill as many members as he can as revenge for Elbert.
Sword of Seals's Gale is the son of Blazing Sword's HeathThis might seem like a long shot, but hear me out. In Heath's nonpaired ending, he relocates to Ilia and continues fighting as a mercenary. In Sword of Seals, the reason Gale is originally denied the position of Dragon General is because he isn't a native of Bern (despite being one of Bern's "trademark" Wyvern Lords). In other words, my theory is that Gale was born in Ilia as Heath's son, and became a wyvern rider like his father, and eventually traveled to Bern and became a Knight.
The Tactician from FE7 is Harry Paget Flashman.Think about it: he does very little actual fighting or real work, letting Lyn handle the bandits in Lyn's Tale. Despite that, he manages to come off as quite the hero, and all the records place him as indispensable to Nergal's defeat, and who knows? Maybe he really was, in the typical Flashman way. And if all the tactician-fics are any indication, he does a lot of unwarranted bragging, especially when it comes to nailing the chicks. All we need now is for some clever bastard to blackmail him into joining Eliwood's little warband, and it all fits together.
Gale from FE6 was supposed to be recruitableLet's list some facts:
Eliwood's stats are usually bad because he's carrying the Tactician into battle.He really IS a good warrior, but his stats are lame compared to Hector's because he has a permanent rescue penalty.
Erk is Niime's grandson and Hugh's cousin.That purple hair. He's a little too old to be Canas's kid, but Canas notes having several brothers, at least one of whom was probably older. But all those brothers ended up soulless husks due to Dark/Elder magic, and given Niime's special child raising practices, it's not too strange to imagine she might have shipped him off to study under Pent.
Lalum is Oujay's sister.In his support conversation with Wendy, Oujay mentions that he had a sister but, because of how poor his village was, female children were usually left in far-off lands to be adopted by people who can give them a better life. Lalum is adopted. This is Fire Emblem, where there are no coincidences; any character mentioned offhand will somehow become important to the plot. (Note that every last character mentioned in a support conversation in Blazing Blade that does not appear in that game does appear in Sealed Sword — Geitz's brother, Canas's mother and son, Hawkeye's daughter, etc.) Note, also, that this is a franchise with a history of adding a bunch of unexpected familial relations between its characters (most notable in Radiant Dawn, but also the whole Nino/Canas thing in Blazing Blade). It would be a unique occurrence if something like this was mentioned and it didn't refer to someone else in the game. Also, in the Lalum/Oujay conversation, Oujay seems pretty uncomfortable with Lalum's flirtatious advances and is specifically trying not to stare. There isn't much that can explain why he would be uncomfortable, but it's possible that something in his subconscious is telling him that starting a relationship with this girl would be a bad idea.
A grown-up Nils will appear in future Awakening DLCThe last time we saw him, he was headed through the Dragon's Gate to a world where humans and dragons co-existed, which many have speculated to be Archanea. Having Nils around as a regular character in Awakening (as opposed to an Einherjar) would be a cool way to follow up on that and give us another view of Elibe's backstory the same way Tiki did for Archanea. Also, two words: Ice Manakete.
Nino is descended from LewynGoes off the "Dragon's Gate leads to Archaneia" theory. Sonia says that Nino's family has been hailed as one of the strongest magic families ever. One of Lewyn's descendants stumbled into Elibe and decided to settle down there, thus beginning that same family. It would certainly explain those fantastic growths and green hair.
Jahn was supposed to be a true dragon...But the writers realized that they hadn't made him powerful enough for it to be believable. The lack of emotion shown by Jahn and the Elder of Arcadia were likewise supposed to be how dragons acted, with Fae and the elder having learned emotion from their time with humans. But then they realized that dragons would have been living with humans before the war, so learning emotions could not have been a new phenomenon. Having realized that it made more sense for Jahn to be a delusional wardragon, they decided to take these implications and expand on them in the prequel, with other true dragons appearing and being a much more legitimate threat.
Hector's Story is the canon version.I'm going to start this off with a gameplay story: On one playthrough of Hector's Story, I had Bartre properly trained, but Karla never appeared; conversely, I also once had her appear when I'd accidentally gotten Bartre killed off. I eventually came to the conclusion that her appearance is contingent on saving the village in Chapter 25 in which she appears and gives the party an Elysian Whip. Hence, it can be assumed that if that village isn't saved, she somehow dies in that bandit attack. Since the party never even goes to that area in Eliwood's Story, they're not around to save that village (which explains why Karla never appears in Eliwood's Story), and as such, Karla dies, which causes continuity problems because it means that she and Bartre never hook up and have Fir. Hence, Eliwood's Story cannot be canon.