a former collective term for the territories under the leadership or control of the British crown, including those in the Commonwealth of Nations and their colonies, protectorates, dependencies, and trusteeships.
(formerly) the United Kingdom and the territories under its control, which reached its greatest extent at the end of World War I when it embraced over a quarter of the world's population and more than a quarter of the world's land surface
The empire of Britain, which began in the sixteenth and seventeenth centuries with the establishment of colonies in North America and ended in the twentieth century as dozens of nations, formerly British possessions, became independent. At the empire's greatest extent, around 1900, it included Australia, Canada, India, New Zealand, vast portions of Africa, and many smaller territories throughout the world. The empire ceased to have an “emperor” in the late 1940s, when the British king renounced the title of emperor of India. The empire has been succeeded by the British Commonwealth, which was formed in 1931.