Numbers 32:28-42

So Moses gave command concerning them to Eleazar the priest, to Joshua the son of Nun, and to the chief fathers of the tribes of the children of Israel. And Moses said to them: “If the children of Gad and the children of Reuben cross over the Jordan with you, every man armed for battle before the LORD, and the land is subdued before you, then you shall give them the land of Gilead as a possession. But if they do not cross over armed with you, they shall have possessions among you in the land of Canaan.” Then the children of Gad and the children of Reuben answered, saying: “As the LORD has said to your servants, so we will do. We will cross over armed before the LORD into the land of Canaan, but the possession of our inheritance shall remain with us on this side of the Jordan.” So Moses gave to the children of Gad, to the children of Reuben, and to half the tribe of Manasseh the son of Joseph, the kingdom of Sihon king of the Amorites and the kingdom of Og king of Bashan, the land with its cities within the borders, the cities of the surrounding country. And the children of Gad built Dibon and Ataroth and Aroer, Atroth and Shophan and Jazer and Jogbehah, Beth Nimrah and Beth Haran, fortified cities, and folds for sheep. And the children of Reuben built Heshbon and Elealeh and Kirjathaim, Nebo and Baal Meon (their names being changed) and Shibmah; and they gave other names to the cities which they built. And the children of Machir the son of Manasseh went to Gilead and took it, and dispossessed the Amorites who were in it. So Moses gave Gilead to Machir the son of Manasseh, and he dwelt in it. Also Jair the son of Manasseh went and took its small towns, and called them Havoth Jair. Then Nobah went and took Kenath and its villages, and he called it Nobah, after his own name.