Britain: Goodbye to All That

In the heyday of empire, British representation abroad often consisted of a well-connected royal appointee ruling one of the crown's dozens of far-flung colonies in style. Throughout the tropics of Asia and Africa, governors-general sweated through noontime heat in white-plumed hats and braided uniforms, lived in white palaces called Government House and spent much of their time hobnobbing with maharajahs, sheiks and local princelings.

With the fading of empire came a new kind of presence, dominated by the Commonwealth Office and Britain's elite, 154-year-old diplomatic corps. The corps' own style, always rigid...