Irtysh Oblast is an oblast in the Matriarchate of Periaslavl. It lies to the far southeast of Periaslavl, bordering Szebenkreisen, Karlkreisen?, and Hanzekantoor to the west and the Empire of Makhaira to the south. It is named for the Irtysh River, which runs through much of the oblast. Its kniaz is Zlatan Akimovich and its largest town is Chelyabinsk.
The banner of Irtysh Oblast consists of three equally-sized horizontal stripes: white on top, blue in the middle, and green on the bottom. The personal standard of the kniaz adds a gold border.