I've got not just one book in the promo spot today, but a whole series. Felicity Pulman's The Janna Chronicles have the most gorgeous covers.

The Janna Chronicles is a six-book medieval crime series set at the time of the bitter and treacherous civil war between King Stephen and the Empress Matilda.
A young woman, along and destitute after the death of her mother, goes in search of her unknown father while vowing to bring a killer to justice. In a country torn apart by war, Janna needs all her wits and courage to stay alive as she comes closer to the truth about her birth and to those who would silence her forever. Vying for her heart are the villain, Godric, the dashing nobleman, Hugh, and Ralph, the charismatic pilgrim - but who can Janna trust when all around her have secrets - and someone wants her dead?
Praise for the Janna Chronicles
This is extremely well written, a compelling mystery with excellent historical background seamlessly woven through the tale. The times were convincingly evoked, and the netherworld inhabited by the skilled herbalist and her daughter Janna on the fringes of a superstitious society whose people yet need her arcane skills is intriguingly realised. The war, beyond the ken of most, yet sometimes impinging unpleasantly on daily life brings an added tension to Janna's quest for survival and for answers about her mother's mysterious death. (Amazon review)
For more about Felicity check out her website.
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