The following is from the book, Indian Wars, by Bill Yenne.
The decisive battle of the Coeur d'Alene War would come two weeks later, on September 1, 1858, on the flat plains west of Spokane. Colonel George Wright led six hundred men drawn from five companies of the 1st Dragoons, five companies of the 3rd Artillery Regiment, and two companies of the 9th Infantry Regiment. Opposing him were a combined force of Yakima, Palouse, Spokane, and Coeur d'Alene, who were confident and ready for battle. Both Kamiakin and his nephew Qualchin, who had been the catalyst for the Yakima War three years earlier, were present.
The Indians attempted to break up the Army force by allowing them to capture a hill, and then drawing them into a series of ravines and woods on the far side, but Wright turned the tables. Wright integrated his various elements masterfully. He managed to draw the Indian line out onto the open hillside, where his cavalry enveloped them, and the artillery blasted the covered positions in the ravines and woods. Since 1856, the standard guns used by the U.S. Army's light field artillery units in the West were the three-inch Rodman Ordnance rifle, and the smooth-bore Napoleon twelve-pounder field gun. The rounds fired included canister or case shot that was particularly effective against massed formations such as those encountered on the Spokane Plain. The infantry were now equipped with the model 1855 rifles, whose long-range accuracy accounted for a significant number of Indian losses. In the Battle of Four Lakes, fifty Indians were killed in action, while the U.S. Army suffered no losses.
Wright kept up the pressure, catching the Indians four days later in another fierce battle. Again, he used his artillery to its full effect, and his cavalry to attack the Indians once they had been knocked off balance by the artillery barrage. The U.S. Army's success in the Battle of the Spokane Plain rounded out the earlier victory at Four Lakes. The Indian force that had been so confident a week earlier was in disarray, and within a few days the Army had rounded up a sizable number of prisoners.
Though there would be a few minor skirmishes in eastern Oregon after the Civil War, Wright's victory at Spokane essentially marked the end of the Indian Wars in the Pacific Northwest north of the Great Basin. Qualchin was captured and executed for his part in the killings in 1855. Kamiakin had been injured by a falling tree branch at Four Lakes, but he was rescued by his wife Colestah. They escaped to Montana, and later Canada. They returned to eastern Washington in 1860, where they lived peacefully. Colestah died four years later, and Kamiakin remained in the area until his death in 1877.