The most favorable political and social context at the beginning of deuteronomic literary activity is the age of Josiah. Like Deuteronomy, so the first edition of Joshua is probably functional to the political intentions of Josiah. The stories of conquests were therefore instrumental to the affirmation of Juda’s political and military independence. To this end, YHWH was attributed the qualities of a national god – as usual among the Assyrians – guaranteeing the political autonomy of his people.
The oldest part of Joshua’s book could be made up of some parts in chapters 5-12. The dominant theme is that the victories of Israel are all due to the intervention of YHWH, true king of Judah. The fact that YHWH will fight for Israel, leaving – so to speak – to Joshua a secondary role and in any case always as leader of Israel is clear in the comparison between Josh 5:13-14 and a report of the campaign of Ashurbanipal against Elam:
Ishtar who dwells in Arbela entered, with some quivers hung on the right and on the left and with a bow in his hand. He had wielded a sharp, pointed sword, ready for battle. You stood before her and she spoke to you like a mother who brought you into the world … you said to her: “Wherever you go, I will come with you.” But the lady of the ladies answered you: “You are here in your place … until I go to accomplish that task.
In the most ancient edition – which Römer identifies in some verses within the chaps. 5-12 – Joshua represents the king as an intermediary between the national god and the people. Who wrote this story presumably lived in the days of Josiah, the king that Joshua embodies. In fact, Josiah and Joshua are names closely related in Hebrew. In this first edition of the book of Joshua, the expansionist policy of Josiah tried to conquer part of the Northern Kingdom under the Neo-Assyrian power (eg Benjamin, immediately north of Judah, cf. Josh 8 and 9).
In Josh 9, the alliance with the gabaonites attests the widespread practice of the neo-Assyrian kings who receive the obedience of the vassal peoples, offering them protection against the enemies who are coalescing against them (see Josh 10). The power of Joshua on the sun and the moon (Josh 10:12-13) would be attributed to the intent of the first dtr to demonstrate the superiority of YHWH – represented by Joshua chosen by him – on the deities of the Assyrian pantheon.
The first edition of Joshua perhaps ended with 11:23 or 21:43-45. According to Römer, chapters 13-19 had a more recent origin. Therefore the first edition of Joshua was particularly influenced – as already the Deuteronomy – by the ideology and the neo-Assyrian political language. The aim was to create a military history aimed at legitimizing the occupation of the country. In this sense, this story is very different from patriarchal stories, for example, where Israel seems almost a native entity (Gn 12-36).
On a historical level, the Jewish conquest of Canaan by the Jews is very unlikely. Probably, the idea of conquest was instead the result of the nationalistic ideology that characterized the deuteronomic circles at the time of Josiah, in the last years of the Kingdom of Judah.