sentences:  Because of the boundary treaty partitioning Okanagan territory, Okanagans south of the line became organized under a new chieftaincy founded by Tonasket, who was not of chiefly lineage but rose to prominence because of his campaigns against the miners travelling the Okanagan Trail.Most American Okanogan people reside at Omak, Washington, or on the Colville Indian Reservation, where they are intermingled with other Salishan peoples of the region.The region of his reign became known as Nicola's Country, with the river that ran through it named for him, and the largest lake and the valley it flows through named for the river, still called in regional English today "the Nicola Country".