It is my understanding that the Neviim has two major divisions:
the Former Prophets (Nevi'im Rishonim נביאים ראשונים, the narrative books of Joshua, Judges, Samuel and Kings) and the Latter Prophets (Nevi'im Aharonim נביאים אחרונים, the books of Isaiah, Jeremiah and Ezekiel and the Twelve Minor Prophets).
With respect to this division, I have two questions:
I understand that the Rishonim writings were, generally speaking, composed much earlier than the Aharonim, and it is this fact that was why I supposed they were divided as the Former/Latter. However, that is only "generally" true, as CashCow reminded me that some of the Twelve are believed to be composed during the time some of the Rishonim were written. This leads to one question:
What are the divisional names of Rishonim / Aharonim intended to reflect? Two ideas seem logical: (a) generally, the period of their writing, or (b) the topic of their content, that is, the Aharonim largely focusing prophetically on the future (latter) days of Israel, while the Rishonim are largely focusing on the historical (former) days of Israel?
What is the earliest known reference to the Neviim having the Rishonim / Aharonim division for organization? That is, do the Dead Sea Scrolls show evidence of this particular division? Apparently there is at least reference to the total body of the Neviim as early as 68 CE in the Dead Sea Scrolls, but is there evidence of organizing them in the two divisions at that time? Or some other early evidence in Rabbinical writings?