Final answer:
A nation-state is a political entity characterized by a shared culture, ancestry, and country. It emerged during the 19th century as a way to unite people with a common national identity.
Step-by-step explanation:
A political entity that is characterized by a common culture, sense of ancestry, and country is called a nation-state. A nation-state refers to a state where the majority of its citizens share a common heritage, culture, language, or religion. This concept of a nation-state emerged during the political revolution in Europe in the 19th century, where the goal was to unite people with a common national identity under a single government.