|Vassal state of Tang Dynasty
independent kingdom de facto
|Religion||Buddhism, Confucianism, Taoism, Chinese folk religion, Korean shamanism|
The kingdom was originally called Goryeo, but later historians added "Lesser" for disambiguation from Goguryeo, which was also often called Goryeo. "Goryeo" is also the name of a later period of Korean history (see Goryeo), and the source of the English name Korea.
After the Korean Silla kingdom and the Chinese Tang Dynasty allied to destroy Goguryeo, the Liaodong Peninsula was briefly administered by Tang. Tang soon lost effective control due to rebellion by Goguryeo refugees, and the region became a buffer zone between Tang and the Korean kingdom of Balhae. Although Lesser Goguryeo declared itself an independent kingdom, it was soon absorbed into Balhae, which became the successor state to Goguryeo. 
In 699, the Tang government sent former Goguryeo Prince Go Deokmu, the third son of Goguryeo's last ruler, King Bojang, to Liaodong Peninsula, naming him "King of Joseon" and Governor of the Yodong Commandery of the Protectorate General to Pacify the East. Like his father, Go Deokmu had plans to rebel against the Tang and revive Goguryeo and provide a kingdom for the Goguryeo people.
The Tang Empire at the time was undergoing several crises, especially the An Lushan Rebellion.Along with these major events was also the pressure given by the Empire of Balhae. These and many other pressures allowed Go Deokmu to take full control of the Protectorate General to Pacify the East and establish a kingdom.
The Little Goguryeo kingdom was established during that year with Go Deokmu as its first king. Very little is known about how the establishment of Little Goguryeo was reacted upon by neighboring kingdoms. It is known that the Balhae was in good terms with Lesser Goguryeo in respect for the similar purposes that the two kingdoms possessed.
At around 820, after two generations of ruling the Liaodong Peninsula and other former regions of Goguryeo, Lesser Goguryeo was absorbed into Balhae during the reign King Seon of Balhae.
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