A massive, multi-national coalition gathers with a single shared goal: to wage war against the Israelites. Rather than a random assortment of enemies, this is a highly organized alliance led by key powers who draw the surrounding peoples into their ranks [מאירי, ביאור שטיינזלץ].
The primary forces spearheading this campaign are the Edomites [אבן עזרא, מאירי]. As an ancient nomadic people known for dwelling in tents [מצודת דוד], they are identified with the inhabitants of Seir from historical accounts [רד״ק]. Their arrival on the battlefield with their tents is a deliberate strategic move. It signals their readiness for a long conflict, preparing to lay a drawn-out siege if they cannot defeat the Israelites quickly [רד״ק]. Alternatively, the focus on their tents simply highlights how they uprooted themselves to settle and join forces with the other nations for this specific mission [אבן עזרא].
Alongside Edom, the Ishmaelites also take a leading role in directing the military campaign [מאירי]. Together with Moab and the rest of the gathered nations, they operate under the broader command of the Ammonites. This leadership structure aligns with historical records of the battle, which specifically highlight the forces of Seir, Ammon, and Moab [רד״ק].
The coalition is further bolstered by the Hagrites, a group of Arab tribes [ביאור שטיינזלץ] who trace their ancestry back to Hagar. The primary approach among commentators is that these tribes descend from children Hagar had with another husband after she was sent away by Abraham [רד״ק, אבן עזרא, מצודת דוד]. They took her name because of her famous status as Abraham's maidservant, choosing to link their historical identity directly to her [אבן עזרא]. A contrasting view, however, suggests that these tribes might actually be the descendants of Abraham himself, based on the idea that Hagar and his later wife Keturah were the same person [רד״ק].