What does Joshua 13:21 mean?

This land included all the towns on the plain and the whole kingdom of Sihon, the Amorite king who ruled in Heshbon. Moses had defeated him, along with the leaders of Midian: Evi, Rekem, Zur, Hur, and Reba, who were Sihon’s allies and lived in that land. Joshua 13:21 - Modern Text Bible

(This verse gives background: Moses had conquered this area from King Sihon and his allies, so it was now available for the Israelites.)