Dist.Ct. erred in granting defendant-Village’s motion for summary judgment in plaintiff-Tribe’s action seeking to enjoin defendant from enforcing its ordinance requiring that plaintiff obtain permit to host plaintiff’s annual festival on land that was partially located in Village, but was entirely located on land that was part of Reservation that was formed by 1838 Treaty with Tribe. While defendant argues that said land was no longer part of Reservation, where Congress had allotted Reservation among individual Tribe members and allowed Tribe members to sell said land to non-Indians, Ct. of Appeals, in reversing Dist. Ct., found that under Solem, 465 U.S. 463, and McGirt, 140 S.Ct. 2452, Reservation could be diminished or disestablished only by Congress, and that Congress, through its statutory text, never articulated clear congressional purpose to diminish Reservation, even though it had allowed Tribe members to sell land to non-Indians. As such, entire Reservation as established through 1838 Treaty remained Indian country, such that defendant lacked jurisdiction to apply its ordinance to plaintiff’s on-Reservation activities.