Coins of Yashovarman
Nothing much is known about the events in Kanyakubja from the death of emperor Harshavardhana in 647 AD up to the rise of the Yashovarman who in the eighth century had established an empire at Kanyakubja which for a while controlled much of the North India. After Harsha's death there was a great confusion due to the absence of his heirs.
After Harsha's death Kanyakubja came for a short period under the hands of an usurper, Arunasva who attacked Wang Hstian-tse who had come to the court of Harsha as ambassador of the Chinese emperor Tai-tsung. However, Wang Hstian-tse, with the help of an army from Tibet, Nepal and Assam, succeeded in capturing Arunasva who was taken back to China to spend his days in attendance on the Tang Emperor.
The city of Kanyakubja, modern Kannauj, was the largest and most prosperous city of Northern India and its cultural centre till the coming of the Muslims.
The exploits of Yashovarman have been documented in the Prakrit poem Gaudavaho (Slaying of the king of Gauda) written by Vakpati who was his court poet. In this work the poet has described the slaying of the king of Bengal by Yashovarman. While Jaina texts Prabhavakacarita, written by Prabhācandra, Prabandha Kosha (written by Rajashekhara Suri) and Bappabhattisuricarita have referred to Yashovarman in glowing terms, the Kashmiri poet Kalhana, in his magnum opus Rajatarangini, has described him as a ruler who was among those defeated by Lalitaditya Muktapida (724-760) of the Karkota dynasty in Kashmir.
British archaeologist Alexander Cunningham believed Yashovarman to be connected to the Maukharis who rose to prominence in the 6th century AD and first gave importance to the city of Kanyakubja.
According to V A Smith, extended the dominions of his empire. However he had to play subservient to Lalitaditya Muktapida.
According to the Nalanda stone inscription, Yasovarman is referred to as the Lokpala, guardian of the world. It describes Yasovarman as the one "who has risen after placing his foot on the heads of all the kings and has completely removed the terrific darkness in the form of all his foes by the diffusion of the rays of his sword and who shines as the refulgent sun in all quarters for awakening the lotus representing the whole earth."
Yasovarman had established relations with China. He had sent Buddhist monk Buddhasena to the Chinese court.
The rapid rise of Yashovarman was accompanied by the rapid decline of his empire.