When were nation-states formed?

Answer 1

Nation-states began to emerge in the late Middle Ages and became more defined during the early modern period, particularly from the 16th to the 18th centuries. The Treaty of Westphalia in 1648 is often cited as a significant milestone in the establishment of the modern nation-state system, as it recognized the principle of territorial sovereignty. Over time, the concept evolved, influenced by factors such as nationalism, colonialism, and the rise of centralized governments. By the 19th century, nation-states had largely become the dominant political entities in the world.