Born of Fire by Kella McKinnon

More than thirteen centuries ago, the Highlands were ruled by a powerful Pictish King whose ferocity in battle was as legendary as his honor and devotion to his people. When his trusted advisor had a vision that the Picts could one day disappear from the Earth, King Bridei charged one family with protecting and preserving the language and lore of the Picts through the generations to come.
Born into this ancient family line, Nessa Brodie feels both the weight of her responsibility and the desire to pursue her own dreams, until a series of fateful events lands her in the distant past. As she navigates her new world and all of the uncertainty and fear that comes with it, Nessa begins to realize that she is destined to be the completion of a circle begun long before she was born. Torn between the life and love she left behind, and the captivating passion of an untamed warrior-king, Nessa learns that even the path laid out by fate is never easy or straight.