He married a wife from the Jin clan, setting a precedent for his successors, and he moved the capital to Hansan, today's southeast Seoul.

[3] According to both Korean and Chinese sources, the first diplomatic contact between Baekje and China took place in 372, when Geunchogo sent a mission to the court of Jin.

In the same year, the Jin court sent a mission granting him the title of the "General Stabilizing the East and the Administrator-General of Lelang" (진동장군 영낙랑태수; 鎭東將軍領樂浪太守).

Baekje established commanderies in the Liaoxi regions of China and advanced into Kyūshū of Japan, and rose as the new trading center of East Asia.

According to Nihon Shoki, Geunchogo also sent scholars Wang In and Ajiki to Japan to spread knowledge of Baekje culture: Confucianism and Chinese characters.

[6] During his reign a history of Baekje titled Seogi (서기; 書記) was compiled by the scholar Go Heung (고흥; 高興).