Founded in 918 during the Later Three Kingdoms period, Goryeo unified the Korean Peninsula until 1392, a feat celebrated as a "true national unification" by Korean historians. This unification was significant as it merged the identities of the earlier Three Kingdoms and incorporated elements from the ruling class of Balhae, a successor of Goguryeo. The name "Korea" itself originates from "Goryeo," a testament to the dynasty's lasting influence on Korean national identity. Goryeo is acknowledged as the legitimate successor to both Later Goguryeo and the ancient Goguryeo kingdom, thereby shaping the course of Korean history and culture.

The Goryeo era, coexisting with Unified Silla, is known as the "Golden Age of Buddhism" in Korea, with the state religion reaching unprecedented heights. By the 11th century, the capital boasted 70 temples, reflecting Buddhism's deep-rooted influence in the kingdom. This period also saw a thriving commerce, with trade networks extending to the Middle East, and the capital city in modern-day Kaesong blossoming into a hub of trade and industry. The cultural landscape of Goryeo was marked by significant achievements in Korean art and culture, enriching the heritage of the nation.

Militarily, Goryeo was formidable, engaging in conflicts with northern empires such as the Liao (Khitans) and Jin (Jurchens) and challenging the Mongol-Yuan dynasty as it waned. These efforts were part of Goryeo's Northern Expansion Doctrine, aiming to reclaim lands of their Goguryeo predecessors. Despite its cultural refinement, Goryeo was able to assemble powerful military forces to resist threats like the Red Turban Rebels and Japanese pirates. However, this resilient dynasty met its end when a planned assault on the Ming dynasty sparked a coup led by General Yi Seong-gye in 1392, concluding the Goryeo chapter in Korean history.