Numbers 32:29; Numbers 32:33

29 He said to them, “If the Gadites and Reubenites, every man armed for battle, cross over the Jordan with you before the LORD, then when the land is subdued before you, you must give them the land of Gilead as their possession.

33 Then Moses gave to the Gadites, the Reubenites and the half-tribe of Manasseh son of Joseph the kingdom of Sihon king of the Amorites and the kingdom of Og king of Bashan—the whole land with its cities and the territory around them.