The largest region of the world by population is Asia, home to 4.545 billionpeople in 2018 (United Nations Population Division). The map above lists the population of each region. The circles show each of the 22 United Nations sub-regions of the world, sized by population. The largest five sub-regions are Southern Asia (1.9 billion people), Eastern Asia (1.7 billion), South-Eastern Asia (656 million), Eastern Africa (434 million), and South America (428 million).