This took place after the defeat ¹  of King Sihon ²  of the Amorites, whose capital was ³  in Heshbon, ⁴  and King Og of Bashan, whose capital was ⁵  in Ashtaroth, ⁶  specifically in Edrei. ⁷ 

The Lord, however, said to me, “Don’t be afraid of him because I have already given him, his whole army, ¹  and his land to you. You will do to him exactly what you did to King Sihon of the Amorites who lived in Heshbon.”

in the Transjordan, in the valley opposite Beth Peor, in the land of King Sihon of the Amorites, who lived in Heshbon. (It is he whom Moses and the Israelites attacked after they came out of Egypt.