For five centuries from 1392 to the arrival of modern imperialism in the late 1800s Korea underwent a continual process of cultural change and integration under the Chosǒn state and its Yi dynasty. ‘A Confucian society’ explains how Confucian-based cultural norms pervaded every social class, giving a greater uniformity and unity to Korean society. The state’s territorial boundaries stabilized to where they are today, its population became ethnically homogeneous, and its culture became profoundly Confucian. The process by which the inhabitants of the peninsula developed into a single people with a shared culture and identity, one clearly recognizable today as ‘Korean’, had begun long before. Under Chosǒn it was largely completed.