Battle of Bear Valley The Battle of Bear Valley was a small engagement fought in 1918 between a band of Yaqui s and a detachment of United States Army soldiers . On January 9 , 1918 , elements of the American 10th Cavalry Regiment detected about thirty armed Yaquis in Bear Valley , Arizona , a large area that was commonly used as a passage across the international border with Mexico . A short firefight ensued , which resulted in the death of the Yaqui commander and the capture of nine others . Though the conflict was merely a skirmish , it was the last time the United States Army engaged hostile native Americans in combat and thus has been seen as one of the final battles of the American Indian Wars . Background . By 1918 the Yaqui people had been at war with Mexico for several years , the former hoping to establish an independent state in Sonora , centered around the Rio Yaqui and its confluence with the Gulf of California . Many Yaquis were driven north by the war and some crossed the Arizona border to work in Tucson ' s citrus groves . After receiving pay , the Yaquis would spend their money on weapons and ammunition and then return to Mexico to continue fighting . The fact that Yaquis were buying arms in Arizona and smuggling them across the border became so well known that the military governor of Sonora , General Plutarco Elías Calles , informally requested help from the United States government in dealing with the problem . Furthermore , Arizona ranchers began reporting in larger numbers their encounters with armed Yaquis on their ranch land or the finding of butchered livestock on the range . Since the United States Border Patrol did not yet exist , the task of protecting the border was that of the army , which operated out of Fort Huachuca . The Nogales , Arizona subdistrict commander , Colonel J . C . Friers , 35th Infantry , responded to the reports by issuing orders to increase patrolling in the area . American forces in the area included the 35th Infantry Regiment , stationed at Camp Stephen D . Little in Nogales , and the 10th Cavalry Buffalo Soldier s , who were spread out to protect the various towns near the international border . A squadron size force from the 10th Cavalry was encamped about a half mile from the 35th Infantry at Nogales and a second squadron split up to occupy Lochiel and Campini . Smaller posts were also established at Arivaca and Oro Blanco and , finally , a troop of about thirty men maintained a camp at Atascosa Canyon , a " " strategic natural crossing " " within Bear Valley . According to Colonel Harold B . Wharfield , who interviewed some of the participants in the Bear Valley fight and published his story in the book " Tenth Cavalry and Border Fights " , wrote that the camp was located in a dangerous " " uninhabited region " " where " " unconfirmed mysterious disappearances " " often occurred and people were advised to travel in groups . The camp was built next to an old homestead and a high ridge to the east , which provided an excellent view of the surrounding flatlands . After the January 1918 New Years Day celebration , Captain Frederick H . L . " Blondy " Ryder and his Troop E , 10th Cavalry , were ordered to occupy the Bear Valley camp for border patrol duty . A signalman was posted on top of the ridge who could communicate via hand signals with one of the sentries placed around the camp ' s perimeter . The rest of the soldiers patrolled the trails leading in and out of the valley , watching for people wandering through the desert . Battle . On January 8 , a local cattleman and owner of the Ruby Mercantile , Philip C . Clarke , rode into camp and told Captain Ryder that his neighbor found the body of a cow in the mountains to the north and that a piece of its hide had been removed for making sandals . It was assumed that Yaquis killed the cow so Ryder strengthened the observation post on top of the ridge by sending up First Lieutenant William Scott and a detail of men equipped with field glasses to watch the trails from a distance . According to Colonel Wharfield ' s book ; " " About the middle of the afternoon Lieutenant Scott signaled attention . Upon acknowledgement from the camp sentry he gave the message enemy in sight , and pointed toward a low ridge west of camp a quarter of a mile or more distant . The sentry hollered to First Sgt . Samuel H . Alexander , who was sitting under a nearby mesquite with several other noncommissioned officers . The shout brought everyone to their feet . On the skyline of the ridge could be seen a long column of Indians [ Yaquis ] crossing to the other side . The horses had been under saddle with loose cinches all day tied up in the corral ; so within a few minutes the troop was mounted . " " By the time the soldiers left camp the Yaquis were no longer in sight but Lieutenant Scott kept pointing so the troop kept moving due south , towards the border fence . When the Americans were finally in position , they dismounted in a " " shallow brushy draw , " " left a guard to watch the horses , and then continued advancing on foot in a skirmish line . Moving forward , the soldiers were nearing the top of a canyon side when Captain Ryder decided to return to the horses , using a different path . On the way down , the soldiers came across " " hastily abandoned packs " " which suggested that the Yaquis were very close and knew they were being pursued . Ryder then continued up the canyon , in a southeastern direction , when suddenly the Yaquis opened fire from concealed positions . The Americans returned fire and a typical Indian war skirmish began . Wharfield wrote that " " the fighting developed into an old kind of Indian engagement with both sides using all the natural cover of boulders and brush to full advantage . The Yaquis kept falling back , dodging from boulder to boulder and firing rapidly . They offered only a fleeting target , seemingly just a disappearing shadow . The officer saw one of them running for another cover , then stumble and thereby expose himself . A corporal alongside of the captain had a good chance for an open shot . At the report of the Springfield , a flash of fire enveloped the Indians body for an instant , but he kept on to the rock . " " Captain Ryder wrote Colonel Wharfield the following for his book : Aftermath . About a week after the engagement , Captain Ryder was ordered to proceed to Arivaca , where the Yaqui prisoners would be held until the army figured out what to do with them . According to Wharfield , the Yaquis proved to be reliable workers and adjusted well to life in the army . Even though they were prisoners , each one received three meals a day , a straw mattress for a bed and a G . I . blanket . Wharfield wrote that the Yaquis ; " " kept the campsite immaculately clean . At the corral nearly any droppings were allowed to hit the ground . During the day the Indians would stand around watching the horses . Whenever a tail was lifted , out they rushed with their scoop shovels and caught it before the manure could contaminate the ground . It certainly helped in the decline of the fly population . " " It was sometime during the stay at Arivaca when one of the Yaquis revealed that they had only opened fire because they thought the Buffalo Soldiers coming at them were Mexicans . All ten of the Yaquis , including the boy , volunteered to enlist in the United States Army but the government had other plans and the prisoners were later sent to Tucson for trial in federal court . Charged with " " wrongfully , unlawfully , and feloniously exporting to Mexico certain arms and ammunition , to wit : 300 rifle cartridges and about 9 rifles without first procuring a export license issued by the War Trade Board of the United States , " " the Yaquis plead guilty and were sentenced by Judge William Henry Sawtelle to a mere thirty days in jail , excluding the boy whose charges were dismissed . Colonel Wharfield wrote that " " the sentence was preferable to the Yaquis who otherwise would be deported to Mexico and face possible execution as rebels . " "