Modoc, Native Americans who occupied parts of what is now California and Oregon. They are closely related to the Klamath, with whom they agreed in 1864 to move to an Ore. reservation. In 1870 a Modoc group, led by Chief Kintpuash (Captain Jack), fled back to northern California. The group was attacked by a U.S. army unit, bringing about the Modoc War (1872–73). Some of the Modoc subsequently returned to Oregon; others were sent to Oklahoma.