The Battle of Little Robe Creek, also called the Battle of Antelope Hills, took place on May 12, 1858. It actually was a series of three distinct encounters that took place on a single day, between the Comanches on the one side, and Texas Rangers, militia, and allied Tonkawas attacking them. It was undertaken against the laws of the United States at the time, which strictly forbade such an incursion into the Indian Territories of Oklahoma, and marked a significant escalation of the Indian Wars. It also marked the first time American or Texas Ranger forces had penetrated the Comancheria as far as the Wichita Mountains, and Canadian River, and it marked a decisive defeat for the Comanches.