When composed of hunter-gatherers, Asia’s population numbered perhaps 1–2 million. But the emergence of agriculture saw population growth, and it appears likely that by 1 CE the continent’s population exceeded 100 million. For China and Japan, there are data which shed light on their population histories during pre-modern times. Moreover, both countries experienced rapid demographic transitions in the 20th century—substantially limiting the associated extent of population growth. For the Indian subcontinent and Southeast Asia, there are almost no population data prior to the late 18th century, although what happened subsequently is better recorded. Both these diverse regions experienced fairly protracted modern demographic transitions and substantial population growth. West Asia’s population is thought to have been of similar size in 1900 as in 1 CE. During the 20th century, however, most countries in West Asia experienced late birth-rate declines and very substantial population growth. Throughout history, the level of urbanization in Asia has generally been extremely low. Nevertheless, the continent contained most of the world’s most populous cities, though that situation changed temporarily in the 19th and 20th centuries. That said, after 1950 mortality decline fueled urban growth. As a result, by 2020 Asia once again contained most of the world’s largest cities, and about half of the continent’s people lived in urban areas. The population history of Asia has generally involved very slow population growth. The main explanation has been that death rates were high, marriage was early and universal, fertility was uncontrolled, and so birth rates were high too. However, research has increasingly suggested that in some areas the levels of fertility and mortality which prevailed in pre-modern times are better described as “moderate” rather than “high.” Moreover, as in Europe, there were regulatory mechanisms which helped to maintain a degree of balance between human numbers and the resource base.