Book excerpt: The life of Harriet Spencer, Countess of Bessborough, was one of both respectability and high scandal. The aristocracy of the eighteenth century were the A-list celebrities of the day; their lives, loves, fashions and misfortunes avidly reported in the press. They dominated the political world as well as the social, and Harriet was at the very heart of this powerful clique. She was born into the wealth and privilege of the Spencer family - and was the great-great-great-aunt of Diana, Princess of Wales. Following in the train of her sister, the charismatic Georgiana, Duchess of Devonshire, Harriet became one of the most glamorous and influential women of the Regency age. At a time when marriage was an aristocratic woman's only career choice, Harriet made an excellent match, to Frederick, Viscount Duncannon. But the marriage proved unhappy and Harriet soon embarked on a series of illicit affairs, including one with the charismatic playwright Richard Sheridan. In Naples she met and fell in love with the handsome young aristocrat Lord Granville Leveson Gower, a man twelve years her junior. And so began the affair that became the last, untold story of enduring love in the Regency period, an open secret within just a tiny circle. It only ended when Granville married her niece, Georgiana's daughter, taking into his care the two illegitimate children he had by Harriet. Harriet's was a life intertwined with public scandal, royal intrigue and high political drama. She was petted and spoiled by Marie Antoinette; she witnessed the French Revolution and George III's madness. She successfully dodged the Prince Regent's amorous advances; quarrelled bitterly with Byron, when her daughter Caroline Lamb embarked on a scandalous affair with him; and travelled through war-torn Europe during the rise and fall of Napoleon. She survived her sister Georgiana by twenty years, living to see the Battle of Waterloo and the coronation of George IV. An Aristocratic Affair opens a window on aristocratic life at its most intimate, and brings one of the Regency period's most colourful characters vividly to life.