Joshua 13:21
And all the cities of the plain, and all the kingdom of Sihon king of the Amorites, which reigned in Heshbon, whom Moses smote with the princes of Midian, Evi, and Rekem, and Zur, and Hur, and Reba, which were dukes of Sihon, dwelling in the country.
Joshua 13:21 belongs to the account of the divided land, giving the description of the inheritance of Reuben east of the Jordan. In that setting it recalls the victory over Sihon and Og, whose former dominion became part of the portion assigned. The town of Salt lies within that Reubenite land east of the Jordan thus described.
The verse also stands within the connected story running from the building of the tabernacle through the sending back of the ark to Israel. For children that whole story is to be retold in simple, pure, connected form. Wars and intricate, complicated narrations needed only by adults are eliminated, while practical moral lessons are woven in where a child could not draw them without a mature mind.