Why did Britain control the world's greatest empire? ‘The Red on the Map’ seeks to answer this question and the related question: what was the British Empire? The British Empire comprised many different peoples and its constituent parts were added over a long period of time. These different parts were ruled in different ways. The settler states were ‘white’ dominions that enjoyed a great deal of autonomy. India and Britain's colonial empire was governed by a small British ruling class and civil service. Other territories were held as Mandates and condominiums, whilst some had no formal part of the Empire but had treaty relations with Britain.