Countries With the Lowest Population Density Mongolia. Vatican City : With a population of around 1,000 people (as per 2017 data), Vatican City is the least populated country in the world. Namibia has... Australia. With a population of fewer than 1,000 people, Vatican City has the smallest population of any... Nauru - 10,756. This is a list of countries and dependent territories ranked by population density, measured … World population percentage by country as of 2017 This is a list of countries and dependencies by population . The country is enclosed within the Italian city of Rome, and is ruled by the Pope. Countries in the world by population (2020) This list includes both countries and dependent … Interestingly, Vatican City is also the smallest country in the world by land area at 0.17 square miles (0.44 square km). 1. It includes sovereign states , inhabited dependent territories and, in some cases, constituent countries of sovereign states, with inclusion within the list being primarily based on the ISO standard ISO 3166-1 . The island nation of Nauru, located in the Central Pacific in Micronesia, is the second least populated... Tuvalu - 11,646. Although Mongolia is ranked as the eighteenth largest country globally, it still tops the list of countries... Namibia. Countries With The Smallest Populations Vatican City - 799. Namibia, in Southern Africa, has the second-lowest population density of any country in the world.