"A deliciously told group biography of the young, rich, American heiresses who married into the impoverished British gentry at the turn of the twentieth century - the real women who inspired Downton Abbey. Towards the end of the nineteenth century and for the first few years of the twentieth, a strange invasion took place in Britain. The citadel of power, privilege and breeding in which the titled, land-owning governing class had barricaded itself...