Twenty-Two Boys at Summer Camp Generated Tribal Warfare in Eleven Days

In the summer of 1954, Muzafer Sherif and Carolyn Wood Sherif rented a 200-acre summer-camp facility in Oklahoma's Robbers Cave State Park, advertised it as a normal scout-style camp, and recruited 22 eleven- and twelve-year-old boys whose families did not know each other. The boys were carefully selected to be as similar as possible — white, Protestant, middle-class, two-parent households — so that any group differences emerging during the experiment couldn't be blamed on background. They were divided arbitrarily into two cabins. Neither cabin knew the other existed for the first week.

When the two groups did finally meet, in week two, it was through a series of competitive games — tug-of-war, baseball, a treasure hunt — for which the camp staff had quietly arranged prizes. The boys named themselves the Eagles and the Rattlers. Within days, name-calling escalated to flag-burning and cabin raids. Each group developed in-group nicknames, mascots, songs, and shared mythology about the deviousness of the other side; in measurements taken at the height of the conflict, 93% of the boys' chosen friends were inside their own group.

Then the Sherifs set the camp's water tank to fail. Then a shared truck refused to start, requiring both groups to pull on the same rope to start it. Cooperation on these "superordinate goals" — problems neither group could solve alone — slowly thawed the hostility. By the end of the third week, friendships were crossing group lines. The Sherifs had run a similar study the previous year that had collapsed when the boys realized they were being manipulated and ganged up on the experimenters; Robbers Cave was the version where the manipulation worked.