Bohai 渤海 (www.chinaknowledge.de)

http://www.chinaknowledge.de/History/Altera/bohai.html

Bohai 渤海 was a native state in the north of modern Manchuria (modern province of Heilongjiang). It flourished during 8th and 9th centuries and was a tributary state to the Tang empire (618-907) in China.