Pyongyang was founded in 1122 BC

https://en.wikipedia.org/wiki/Dangun the "grandson of heaven" and "son of a bear", and to have founded the kingdom in 2333 BC.

his grandfather Hwanin (환인/桓因), the "Lord of Heaven". Hwanin had a son, Hwanung (환웅/桓雄), who yearned to live on the earth among the valleys and the mountains. Hwanin permitted Hwanung and 3,000 followers to descend onto Baekdu Mountain, where Hwanung founded the Sinsi (신시/神市, "City of God"). Along with his ministers of clouds, rain and wind, he instituted laws and moral codes and taught humans various arts, medicine, and agriculture.[2] Legend attributes the development of acupuncture and moxibustion to Dangun.[3]

In 668, Pyongyang became the capital of the Protectorate General to Pacify the East established by the Tang dynasty of China. However, by 676, it was taken by Silla. https://en.wikipedia.org/wiki/Book_of_Wei