In 1855 Kamiakin convened a council in Eastern Oregon, with representatives from all of the tribes in the Grande Ronde Valley, in order to discuss how best to deal with the invaders and keep their lands. Governor Stevens learned of the meeting when Lawyer, a Nez Perce, informed him of the decisions made there. At the subsequent Walla Walla Council, when Kamiakin arrived, he noticed the large number of Nez Perce and U.S. Government officials, and realized his confidences had been betrayed. Stevens had used the information about the earlier meeting to marshal support for establishing reservations among the wavering tribal factions. When Oregon's Superintendent of Indian Affairs asked Kamiakin to speak, the proud Yakama refused. The other chiefs eventually pressured Kamiakin into signing the treaty "as an act of peace;" it established the Yakama reservation.