Moses summarized the eastern campaign in the book of Numbers after the campaign, providing additional details to the eastern wars in Deuteronomy 1:6–46 and 2:1—9.
The first king and empire engaged in the eastern campaign was King Sihon of Heshbon. Sihon was cataloged as a king of the Amorites. He dwelled in Heshbon but reigned from Aroer positioned across the Arnon River, which was regarded as an outer boundary to the Bashan region. Aroer was Sihon’s royal city where Israel camped opposite thereof, when they requested safe passage through Sihon’s empire, but Sihon refused. As with Sihon, God ensured that the Rephaim kings would be foolish and try to wipe Israel from the face of the earth: “For it was of the Lord to harden their hearts, that they should come against Israel in battle, that he might destroy them utterly, and that they might have no favor, but that he might destroy them, as the Lord commanded Moses.” The notorious Sihon and his empire were sentenced to be utterly destroyed/charam, by their refusal to let Israel pass.
Sihon and Og headlined the lists of infamous conquered kings that Psalm 136 proclaimed for following generations to contemplate. Once more the English translation does not fully convey from Hebrew the larger context to the passage. Great/gadowl is defined as older, haughty, proud, large in magnitude, and mighty, deriving from gadal meaning made large as in a body, proud, one who does great things, and powerful. Famous/‘addiyr is defined as wide and generally large, powerful, glorious, a mighty one, a noble and a majestic one. Both Hebrew words describe giants akin to the Terrible Ones who were ruthless, strong, large and stout and used language akin to the Nephilim mighty ones and men of infamy in Genesis 6:4. Yet the language drafted in Psalm 136 was targeted at postdiluvian giants, to ensure they were not confused or conflated with their antediluvian predecessors.