Judges 5, the Song of Deborah, is widely judged by philologists to be among the oldest surviving pieces of Hebrew literature, on linguistic grounds independent of the prose narrative: its archaic grammar, vocabulary and poetic structure resemble Late Bronze and early Iron Age Canaanite verse more closely than they resemble the prose that frames it in Judges 4, which most scholars regard as a later retelling in more conventional narrative Hebrew. That the poem is older than its prose companion is close to consensus; what it is evidence of is not.
The two chapters disagree in ways that matter. The poem names six tribes answering Deborah's call, Ephraim, Benjamin, Machir, Zebulun, Issachar and Naphtali, and rebukes four others, Reuben, Gilead, Dan and Asher, for staying away, a roster implying a looser tribal confederation than the crisp muster of the prose account. The poem also has Sisera killed while standing, struck as he drinks, where the prose has him already asleep, the kind of detail suggesting two independently transmitted memories rather than one account summarizing the other.
Where scholars divide is over how much history sits underneath the poetry. Finkelstein and Silberman read the Song as a genuine composition close to the events it describes, evidence some real clash between Canaanite forces and a coalition of highland tribes occurred roughly when Judges assigns it, while treating the numbers and much prose elaboration as later literary shaping rather than reportage. Others read the poem's antiquity as evidence only that the poem is old, not that the battle happened as described. Deborah, present in both layers, sits at the center of a case where the material is old but the history it records remains unsettled.