original: Kievan Rus' ultimately disintegrated and the lands were divided into many small feudal states.
simplifications: Kievan Rus' stopped existing and the lands were divided into many small states. Kievan Rus' disintegrated and the lands divided into feudal states. Kievan Rus' eventually ended. At that time, the lands were split into many small feudal states. Kievan Rus' ultimately ended. The lands were divided into many small feudal states. Kievan Rus' was disintegrated while the lands were divided into small feudal states. Kievan Rus' fell and the lands were divided into many small states. Kievan Rus' fell apart. The lands were divided into smaller feudal states. Kievan Rus' fell apart. The lands were divided into many small feudal states. Kievan Rus disintegrated and the territories were split into many small states. Kievan Rus' eventually broke up and the lands were divided into many small feudal states.