Cattlemen of the Big Horn Basin dominated the range for many years and established boundaries, or "deadlines," where sheep were forbidden. Fierce animosity grew between sheep and cattle ranchers as several sheep camps were raided during the late 1800s and early 1900s. In late March 1909, Joe Allemand, a French sheepman, and Joe Emge, a cattleman turned sheepman, left Worland for Spring Creek with 5000 sheep, accompanied by Allemand's nephew Jules Lazier and two sheepherders, Bounce Helmer and Pete Cafferal. As word spread across the western slope of the Big Horn Mountains that the deadline had been crossed, plans were made to stop the intrusion. On the moonlit night of April 2, 1909, seven masked riders approached the camp's two wagons where the herders slept, and gunfire erupted. Emge and Lazier were killed in their wagon, both wagons were set afire, and Allemand emerged from the flames only to be quickly shot down. Five of the perpetrators were convicted and sent to prison, and public reaction against the brutal attack made clear that violence on Wyoming's open range would no longer be tolerated.