Lady Knight by Tamora Pierce

Kel, who fought to be allowed to train as a knight, is finally knighted and sent into the wider world to lead and protect, confronting entrenched prejudice, political intrigue, and brutal threats such as slavers and raiders; tested by moral dilemmas and the harsh realities of command, she must balance duty, compassion, and tactical skill as she grows into the courageous, principled leader she aspired to be while defending the vulnerable.

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