This appointment of vice shogun was done before the appointment of shogun, a commander in chief of the army to subdue the eastern barbarians, and next year of the appointment of vice shogun, OTOMO no Yakamochi was appointed as Jisetsu Seito Shogun (the general of conquering east-barbarians) and sent punitive force of Ezo.
この副将軍人事は、征東軍の総司令官たる将軍人事よりも前に行われており、副将軍人事の翌年に大伴家持が持節征東将軍に任ぜられ、蝦夷討伐の軍を発している。