Editing Balhae (section)

=== First Phase ===
The first phase was a period during which the overall system was established, and this period firmly retained the legacy of Goguryeo, with military and administrative functions often overlapping. Volume 193 of ''[[Ruijū Kokushi]]'' records that "Balhae spans 2,000 li in all directions, and no prefectures or counties exist. Villages are scattered throughout, mostly Malgal settlements. The people are mostly Malgal, and few are native. All the natives are made village chiefs, with large villages appointing a Dudu/Dudok (都督, Governor) and smaller ones appointing a Cishi/Jasa (刺史, Prefect), while the rest of the leaders are called Shouling/Suryong (首領, Chiefs)." The Dudok or Jasa were likely regional administrative officials of Balhae, such as the Yakheolju Dudok, Mokjeoju Jasa, and Hyeontoju Jasa. Since this was an early period when the system was still being established, remnants of the former Goguryeo dynasty's institutions were still present in many areas, and the division of the entire country was still incomplete. Therefore, in military terms, troops were dispatched mainly to tense situations.

Through the continued territorial expansion during the reigns of King Go and King Mu, Balhae's territorial boundaries were secured, and the government structure was reorganized and completed by acquiring territory, population, and tax revenues. Considering that the initial military force at the time of Balhae's founding was only a few thousand, Balhae likely needed to make overall adjustments to the expanded territory and population. Balhae, which had borders with powerful neighboring states like the Tang Dynasty, the Turks, the Khitans, the Heishui Mohe, and Silla, faced deteriorated relations with its neighbors due to its early aggressive conquests. Moreover, having witnessed the fall of Goguryeo, the dominant power in the previous era, Balhae needed to strengthen and reorganize its military. Therefore, this period can be seen as when Balhae laid the foundation for establishing a new system based on Goguryeo's legacy over the expanded territory.