During the post-Civil War Gilded Age, more than 100 young American heiresses married members of the British aristocracy, bringing much-needed money to the cash-poor earls, dukes, and barons in exchange for titles and prestige. Said to have inspired Downton Abbey, this juicy history of that social phenomenon is as fascinating as it is entertaining, featuring profiles of larger-than-life historical figures, insight into two societies in upheaval, a guide to the finer points of Victorian and Edwardian etiquette, and a satisfying smattering of gossipy anecdotes.