Chief Kintpuash, commonly referred to as Captain Jack, led a group of Modoc people during the Modoc War, which took place between 1872 and 1873 in northern California and southern Oregon. This conflict arose in the context of increased pressure on tribal lands from settler expansion and policies that forced the Modoc into reservations. Tensions escalated following a series of broken treaties and unfair land allocations, culminating in armed conflict. The Modocs, skilled in their rugged terrain, resisted encroachment fiercely, employing guerrilla tactics against a much larger U.S. Army force.

In June 1873, Chief Kintpuash and several other leaders were captured after negotiating a peace settlement, which ultimately failed. They were tried for the murder of General Edward R.S. Canby, who had been leading peace negotiations when he was killed. On October 3, 1873, Kintpuash and three of his companions were executed by hanging at Fort Klamath, Oregon. Their deaths symbolized the U.S. government's resolve to quell resistance from Native American tribes and represented a significant and tragic turning point for the Modoc people.

The aftermath of the executions led to the further dismantling of Modoc society and the dispersion of their tribes. Captain Jack became a controversial figure, celebrated by some as a brave warrior standing up against oppression and vilified by others as a perpetrator of violence against U.S. forces. The Modoc War and the fate of its leaders sparked prolonged discussions about Indigenous rights and the U.S. government's policies toward Native American tribes.