A state is an independent political entity with sovereignty over its internal and foreign affairs. There are currently 191 UN member states. Some areas have unclear or disputed statehood, such as Korea, which is divided between North and South, and Taiwan, which is claimed by China. Western Sahara's status is also disputed, as Morocco controls most of it but the Polisario Front controls parts outside Morocco's defensive wall. State sizes vary greatly, from large countries like Russia and Canada to microstates like Monaco. The concept of the modern state is relatively new, having evolved from earlier systems like city-states, empires, and tribes. Colonialism beginning in the 1400s led European powers to establish colonies in other parts