Goodreads description:

Enchantment is the story of a Ukraine-born, American grad student who finds himself transported to the ninth century to play the prince in a Russian version of Sleeping Beauty. Early in the story, he muses that in a French or English retelling of the tale, the prince and princess would live happily ever after. But, "only a fool would want to live through the Russian version of any fairy tale."

Although his fears turn out to be warranted, as he and his cursed princess contend with the diabolical witch Baba Yaga--easily Russia's best pre-Khrushchev villain--to save the princess's kingdom, Enchantment is ultimately a sweet story. Mixing magic and modernity, the acclaimed Orson Scott Card (Ender's Game) has woven threads of history, religion, and myth together into a convincing, time-hopping tale that is part love story, part adventure. Enchantment's heroes, "Prince" Ivan and Princess Katerina, must deal with cross-cultural mores, ancient gods, treacherous kinsmen (and fianceés), and ultimately Baba Yaga herself.