The Last Warrior (The Lost Clan #4)
Karen Kay

In 1892, that warrior is Black Lion.
There was only one way for Black Lion to melt the Thunder god's anger: Listen for a sacred white man's song—and sing it perfectly with the one who introduced him to it. He joins Buffalo Bill's Wild West Show and travels to London, where he encounters the daughter of two opera singers—the most beautiful woman he's ever seen. However, Suzette Joselyn is already engaged to another man.
But the two are destined to meet again when Suzette shows up in America, pregnant and abandoned by her fiancé. Reunited with Black Lion, she finds it impossible to turn down his offer of marriage to save her child from life as a bastard. But she doesn't realize that her brave new husband is consumed with a mission that may force him to choose between his people and the woman he loves.