In the aftermath of the Great War, the strict hierarchies of the British class system were weakened, and for some ambitious women, this was the chance they needed to slip through the cracks and take their place at the top of society as the great hostesses of the time. Here Sian Edwards offers a colorful group portrait of Lady Astor, who went on to become the first female MP, and Mrs. Greville—a friend of Edward VII—as well as Lady Londonderry, Lady Cunard, Laura Corrigan, and Lady Colefax.