Not strong in spite of the genre. Strong because the author wrote them that way.
The conversation around strong female characters in epic fantasy often focuses on the wrong things. A character is not strong because she can fight. She is not strong because she says sharp things in throne room scenes. She is not strong because she refuses to be defined by her relationships. These are surface qualities. A genuinely strong female character is strong in the same way a genuinely strong male character is strong: she has interiority, her choices emerge from who she is rather than what the plot needs, and her failures matter as much as her victories.
Epic fantasy has produced a number of these over the years. Robin Hobb's Molly is strong precisely because she is ordinary in the ways most fantasy heroines are not allowed to be. Jorg Ancrath's absent mother in the Broken Empire is strong in retrospect, through the shadow she casts on the story. The female characters in the First Law universe are strong because Abercrombie refuses to let them be decorative — they have agency that the world's grinding realism does not override.
Jean Lowe Carlson's Kingsmen Chronicles belongs in this category. Olea den'Alrahel — Captain-General of the Palace Guard, twin sister of the main protagonist Elohl — is a warrior and a strategist who has spent her career operating inside an institution that is being corrupted from its own leadership. Her strength is not defined by her combat ability, though that is real. It is defined by what she does with the access her position gives her: she sees the conspiracy before anyone else does, she makes decisions about what to protect and what to sacrifice, and she carries the weight of those decisions across three books without the narrative suggesting she is extraordinary for doing so. She is doing her job. The job is harder than anyone outside the palace understands.
Ghrenna, the spy and secondary POV, is a different kind of strong. She has been embedded in enemy territory under a false identity for years. She carries a prophetic wyrric gift that shows her things she does not want to know. Her strength is the sustained, unglamorous kind: the ability to maintain a cover, manage intelligence, and function under conditions that would break most people, while also processing visions that implicate events she has not yet lived through. She does not get credit for this from the people around her. She does it anyway.
The Queen — also a POV character in certain sections — is fighting a different battle: the political survival of a throne that is being slowly emptied of its authority. Her strength is diplomatic and strategic, operating in the tradition of political fantasy heroines who have to win without the weapons their male counterparts can use.
All three of these characters are at the center of the story. None of them exist to serve Elohl's arc. The story is, in significant part, about what they do and why — which is the simplest definition of a strong female character that actually means something: she matters to the plot in a way that is not contingent on a male character's existence.
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