Sihon had seized the land of Moab N of the Arnon, and apparently he dominated Midian, for the chieftains of Midian are called “the dukes of Sihon.” (Nu 21:26-30; Jos 13:21)

Sihon’s land was divided among the tribes of Reuben and Gad.​—Nu 21:25, 31, 32; De 29:7, 8; Jos 13:8-10, 15-28.

In the plain, “the tableland of Medeba,” flocks of sheep and goats find pasturage.​—Jos 13:9, 16.

Land is apportioned among tribes of Israel (13:1–22:34)

Moses granted this request to them (and half the tribe of Manasseh) on one condition, that the fighting forces of these tribes also cross over the Jordan and assist the other tribes in the conquest of Canaan, a condition that the two and a half tribes willingly met.​—Nu 32:1-38; Jos 1:12-18; 4:12, 13; 12:6; 13:8-10.

It extended from the torrent valley of Arnon, a natural boundary that separated this territory from Moab on the S, to just N of the Dead Sea; the land N of Reuben was given to the Gadites. (Nu 34:13-15; De 3:12, 16; 29:8; Jos 13:15-23; 18:7)

When the various tribes received their land inheritance in the Promised Land (Jos 13-19), there was no “tribe” of Joseph.

This first conquest thereafter became the territory of the tribes of Reuben and Gad.​—De 3:16; Jos 12:1, 2; 13:8, 9, 15-28.

Thereafter it passed to the tribe of Reuben, although the tribe of Gad is mentioned as building (probably, repairing) the city. (Nu 32:33, 34; De 3:12; Jos 13:8, 9, 15, 16; 1Ch 5:8)

At the time of Israel’s conquest of the Promised Land, the tribes of Reuben, Gad, and the half tribe of Manasseh had been granted the right to receive their inheritance of land “from the side of the Jordan toward the sunrising.” (Nu 32:1-5, 19, 33-42; 34:14, 15; Jos 13:8-13, 15-32)

These, and 42 other cities and their surrounding agricultural land, were allotted to the tribe of Levi.​—Jos 13 to 21.