The Bartered Bride by Mary Jo Putney

After building a fortune amid the splendor and dangers of the China seas, American adventurer and merchant prince Gavin Elliott is sailing for London, where he intends to establish himself in the society that forced his family to leave in disgrace when Gavin was only a child. But fate intervenes on an infamous island in the East Indies when he tries to save a European woman being sold at a slave auction. By the sultan’s decree, the woman can only be freed if Gavin wins her by enduring an ancient tribal challenge that may cost him his life. Yet Gavin cannot refuse to help a countrywoman, especially one who touches his heart and soul with her indomitable spirit. Alexandra Warren ventured to Australia as a young bride eager for adventure. A dozen years later she is returning home as widow and mother when a pirate attack separates her from her beloved daughter and condemns Alex to a life of servitude. Then a miracle arrives in the form of a steely-eyed Yankee captain willing to risk everything to set her free. A shocking turn of events brings an unexpected alliance with her rescuer, and Gavin and Alex arrive in London as intimate strangers joined by too many painful secrets. Yet attraction and affection soon overcome the trauma of their first meeting. Until the past reaches out to change Gavin’s life–and threaten the passionate love he has found with his irresistible bartered bride.