The British Empire expanded dramatically between the 16th and 20th centuries through exploration, trade, and conquest. At its peak in the early 20th century, it was the largest empire in world history, controlling nearly a quarter of the world's land and population. However, nationalist independence movements grew across its colonies in the aftermath of World War 2. Many former colonies, such as India and African nations, achieved independence in the mid-20th century, marking the decline of the British Empire. By 1997, only a few small overseas territories remained under British control.