Mistress Wilding — Rafael Sabatini

To save her craven brother's hide, Ruth promised Wilding she'd marry him. She never guessed she'd fall in love with him . . . Though that she should have known. He was a good man, a fine man, and brave, too. Never in her life could she have imagined that she'd set events in motion that made crowned heads rest uneasily, nor that she'd imperriled all their lives.