1. Korah, Dathan, Abiram and On turned against Moses. (Korah was the son of Izhar. Izhar was the son of Kohath, and Kohath was the son of Levi. Dathan and Abiram were brothers, the sons of Eliab. And On was the son of Peleth.) Dathan, Abiram and On were from the tribe of Reuben.
2. These 4 men gathered 250 other Israelite men and challenged Moses. They were well-known leaders chosen by the community.