 After the fall of Busan, the Japanese army had to secure their bridgehead, because ten kilometres to the north of Busan lay the fortress of Dongnae, a certain type of castle that was situated within a very strong position atop a hill, that dominates the main road north towards Hanseong.Dongnae was a walled citadel on a hilltop commanded by the 41-year-old prefect, Song Sang-hyeon, and the castle was packed with over 20,000 soldiers, poorly trained and equipped conscripts, and panicked civilian refugees from Busan and surrounding areas.After resting overnight at Busan, the First Division left at 6