Emissary to Tang China was Ambassador Fujiwara no Kiyokawa and Vice Ambassador Otomo Gomaro, Japan was seated second on the west side and Tibet was first. Silla, on the other hand, was seated first and Arabia second on the east side. A Japanese historical document describes how the Vice Ambassador Otomo solemnly protested th seating arrangement in front of all delegations by stating that "Sila has been a tributary state of Japan from long ago" and requested for a change in seating order. Fujiwara no Kiyokawa had full power during the reign of Em press Koken, who ruled Japan from 7 to 762; he ordered the building of 500 warships to conquer Silla, trained solders, and planned to educate translators in the Silla language. His plans did not come to fruition, but Japanese anti-Silla sentiment can be inferred from this, Japan, burning with resistance against Silla, sent tions back and forth between Japan and Balhae by the opening of the waterway between Tsuruga in Hokuriku and Duman River (Tumen in Ch). This waterway was also used as one of the paths for River delegations to reach Changa n in China as well as for contacting Confucian scholars The first time Balhae sent a delegation to Japan was in the year 727. The 24 members of the delegation landed Bio (today's Hokaido region), during which 16 people including Chief Envoy Ko In-ui and the eight survivors including Ko Jae-deok (delivered a message o the Japanese Emperor in Nara from the Great King M the second sovereign of Balhae. A Japanese historical document entitled Chronidey Japan H contains the following excerpt Muye has humbly unified jebeon , and has reclaimed the old territory of Goguryeo and preserved the old customs of This shows that the Balhae people prided themselves on having descended from Goguryeo and Goguryeo also claimed itself as an old extension of Buyeo.