[Warning: The following contains major spoilers from the Vikings midseason finale.]

Vikings' midseason finale did not disappoint. Battles were had. Secrets were revealed. Relationships were mended. But one character's fate remains unknown, even after the massive time-jump.

Could Lagertha (Katheryn Winnick) really be dead?

To get the answer to this and more Vikings burning questions, TVGuide.com spoke with creator Michael Hirst.

Lagertha's fate revealed: The last we saw Lagertha in the finale, the shieldmaiden had been stabbed brutally in the chest during the siege on Paris. She doesn't appear in the flash-forward, nor is she mentioned. Has Lagertha gone to Valhalla?

"No," Hirst reveals. "There's a feminist collective in New York who wrote to me a couple years ago and they said, 'We don't' care how many of the male characters you kill off, but if you do anything to Lagertha, you're in trouble.' So I'm very careful about that warning."

More seriously, Hirst says Lagertha is far too important of a character for him to kill her off just yet. "She's also gone on this amazing female journey in which she's gone from farmer's wife [who's] happily married with kids, to being betrayed, to being in an abusive relationship, to having power, to having power taken away from her by men, to having to fight her way back, to having to lose her baby again," Hirst says. "She is the soul of the show and I need her."

Katheryn Winnick, Vikings Photo: History

The rise of Rollo: Hirst never considered killing off one of the Lothbrok brothers in the midseason finale, instead choosing to use the battle as a means to contrast Ragnar (Travis Fimmel) and Rollo's (Clive Standen) surprising paths. "Who would have anticipated, following Rollo's career and life, that he would eventually emerge triumphant?" Hirst says. "I think Clive felt he was always going to be the disappointed and failed younger brother. And I [told him], 'No, actually historically speaking you end up in a good place.' I don't think Clive quite believed me."

"People are rooting for Ragnar and Ragnar's a sensitive guy and a beautiful guy and Rollo's not," Hirst continues. "And yet, when Rollo succeeds and second-guesses Ragnar, I think people are quite pleased for him. I felt quite pleased for him. When he's crowned and when the French Emperor says, 'Hail Caesar' I feel good for him."

The fall of Ragnar: Having suffered his first major defeat - and at the hands of his brother, no less - the drug-addicted Ragnar is brought to his lowest point yet in the finale. But despite the king's unceremonious return to Kattegatt after years away, Ragnar won't be a fallen hero for much logner.

"If you knew what I know about what happens to Ragnar in the second half of the season, you, too, would be very happy that he didn't die [during the fight with Rollo]," Hirst says. "I think Travis is absolutely amazing on this journey and more powerful than ever. What happens to him is unbelievable. Prepare to shed a lot of tears, I think."

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Watch out for Ivar: The end of the finale jumps ahead six years to when Ragnar's sons Ivar (Alex Hogh Andersen), Ubbe (Jordan Patrick Smith), Hvitserk (Marco Ilso) and Sigurd (David Lindstrom) are now full-grown men — each of whom have a very different reaction to the prodigal father's return.

"Some of them are bitter about it. Some accommodate it. But when Ragnar comes back, they're confronted by a lot of issues," Hirst says.

When Vikings returns, the sons will all move into central roles in the series. And though most grew up barely knowing their father, "all of them have a part of Ragnar in them," Hirst says.

"They're all different, but obviously, the most striking of them is Ivar," he adds. "We know the only thing the historical Ragnar was really afraid of is that his sons would become more famous than he was. ... Ivar the Boneless is probably the most famous of all vikings. He's a cripple, and yet he becomes this dominant, extraordinary alpha-male."

Magnus who?: Although Ragnar will finally learn of his son with Kwenthrith (Amy Bailey), this won't be the main reason he'll set sail for England once more. "I think at a deeper level, the connection he's made is not with his unknown son, but is with King Ecbert (Linus Roache)," Hirst says. "They have something in common that no one else on the show had, and I wanted to see them together again, talking about important things. And that's really the motivating factor for Ragnar to go to England [in the second half of Season 4]."

What did you think of the Vikings finale?