The Bear and the Nightgale is a medieval Russian fairy tale-esque novel by debut author Katherine Arden.
And it's beautiful.
That's pretty much the whole review I want to give this book. It's beautiful. It's an experience. You should absolutely read it.
The closest comparison I can think of is Uprooted by Naomi Novak, for the same dark fairy tale feel. The Bear and the Nightingale is something of a slow burn book, about a family living in Northern Russia, and particularly about their youngest daughter, Vasya, who loves to run wild in the forest and sees the creatures of folklore all around her.
The novel juxtaposes Vasya and her stepmother, Anna, two young women who have the sight. Vasya embraces the creatures as protectors of the land and her friends, while Anna sees them as demons, and throws herself into religion to try and escape them. Then a young charismatic priest, Konstantin, comes to the village, and decides that he's been called by God to rid these people of their old-religion superstitions and fill them with fear of God's wrath. He reviles Anna, who wants nothing more than to be his disciple, and is obsessed with Vasya, who he increasingly sees as a witch. When Konstantin's fear allows a dark force to awaken in the forest, Vasya must fight to protect the magic that protects them all.
The Bear and the Nightingale is a book of wild forests, dark creatures, unsettling promises, and complex characters. It's a story of magic, of wonder, of fear, and of not fitting in, beautifully imagined and enchantingly told. I really recommend it.