After describing (at length) the division of the spoils from the war against Midyan (Bamidbar 31:25-54), the Torah tells us of the request made by the Tribes of Gad and R’uvein, when they asked to receive the territory on the eastern side of the Jordan River as their “inheritance.” With no apparent reason to assume otherwise, the order and placement of these two narratives is likely based on when they actually occurred. However, the land of Sichon and Og (which they were requesting) had been conquered well before the war of retribution against Midyan; the involvement with Midyan only came about because Moav was upset/concerned that the Nation of Israel was camped at its border (22:4), which only occurred after the land of Sichon and Og had been conquered (22:2). Why did Gad and R’uvein wait until after the war with Midyan to ask Moshe if they could receive their portion from lands conquered earlier? (Alternatively, if they did ask earlier, why does the Torah tell us about it after the spoils from the war against Midyan were delineated?)
My beloved chavrusa, R’ Yitzchok Steinfeld, told me an answer that was suggested by his rebbe, Rav Yisroel Belsky, sh’lita, which is based on the Tribes of Gad and R’uvein wanting to inherit the land in which Moshe would be buried (see Rashi on D’varim 33:21; see also http://www.aishdas.org/ta/5766/sukkos.pdf). Since G-d had commanded Moshe to “exact revenge against Midyan and then be gathered unto your people” (31:2), it was only after Moshe had fulfilled the commandment — and his death was imminent — that requesting the land became a pressing matter.
Other possibilities are based upon the reason given for Gad and R’uvein making their request — having much cattle (32:1). The spoils from the war against Midyan included a lot of cattle (31:32-34), meaning that as much as each Tribe had before the war, they had that much more after the war. However, since this increase should have applied equally to all the Tribes, the question (if we are to attribute the request made by Gad and R’uvein to their getting more cattle from the spoils of the war against Midyan) becomes why an increase in the amount of cattle for all the Tribes caused these two to make their request.
Daas Sofrim suggests that even though each Tribe received an equal amount of the spoils (including the animals), the other Tribes were not as skilled at shepherding as the Tribes of Gad and R’uvein. Therefore, all of the animals obtained from the spoils (or at least a good portion of them) were sold to Gad and R’uvein, with the net result being that these two Tribes ended up with the overwhelming majority of the nation’s cattle, which led to their request to settle on the eastern side of the Jordan. Maharzo (Bamidbar Rabbah 22:8) says that the Midyanites had exceptional success at animal-rearing because G-d had assigned the administering angel that oversees this to Midyan. When G-d wanted Gad and R’uvein to experience this success, He had the Nation of Israel defeat the Midyanites and reassigned this administering angel to help the Tribes of Gad and R’uvein instead. According to this, it was not the cattle taken as spoils that gave Gad and R’uvein so much more than the other Tribes. Rather, after the war (as a direct consequence) they had much more success with their cattle than the other Tribes did, which led to their request. [Even though there doesn’t seem to be enough time between the war against Midyan and Moshe’s death for these Tribes to have had enough success to need the grazing land on the eastern side of the Jordan, they may have seen what was starting to happen and realized that they eventually would. It should be noted that the wording of the verse is that they “had” much cattle, not they “would have” a lot of cattle in the future.]
A simple, straightforward possibility is that Gad and R’uvein had more cattle to start with, with the increased amount each Tribe obtained after the war just putting these two Tribes over the top. However, if anything, the increased cattle received by each Tribe lowered the percentage gap between the other Tribes and them; a request to receive land on the eastern side of the Jordan should have applied more before the war than it did afterwards. Nevertheless, there might be a very good reason why each and every Tribe receiving a large amount of cattle from the spoils of the war with Midyan led to the Tribes of Gad and R’uvein asking that they be given the land conquered from Sichon and Og.
Previously (http://rabbidmk.wordpress.com/2010/07/21/parashas-va-eschanan-5770), I suggested that even if Gad and R’uvein hadn’t asked for this land, they would have received it as their portion. They knew it would eventually be theirs, and were asking that it become theirs now rather than having to cross the Jordan with their families and belongings just to cross back over after everything was conquered and distributed. This is why, when the lottery that determined which portion of land went to each Tribe was drawn, all 12 Tribes were represented (see Rashi on Bamidbar 26:54), not just the 10 whose lands had not yet been specified. It is also why Moshe gave half of Menashe their land now even though they didn’t ask for it; since both Moshe and Menashe knew it would eventually be theirs, how could Moshe make them schlep everything back and forth if Gad and R’uvein didn’t have to?
Knowing that their portion would be on the eastern side of the Jordan River may have been enough incentive to ask for it now, but after every Tribe received a large amount of cattle from the spoils, they became concerned about whether they would ever really get it. After all, until now it had been clear to all, based on the large amount of cattle they had, that they needed the exceptional grazing land on the eastern side of the Jordan; there was no reason to think any other Tribe would also want to be outside Canaan. However, now that every Tribe needed grazing land, maybe they would also ask for part of the territory conquered from Sichon and Og (see Netziv on 32:5). Moshe wouldn’t be around to insist on giving Gad and R’uvein their rightful portion; would the “new regime,” led by Y’hoshua? Or would they give each of the 12 Tribes a portion on the western side of the Jordan along with a tract of grazing land on the eastern side (similar to the way Yaakov used Sh’chem for grazing while living in Chevron)? Fearful that now every Tribe might want a piece of “their” territory, Gad and R’uvein approached Moshe and asked that it be designated for them, and only them, right then and there.
This could also explain why, seemingly smack in the middle of the conversation (32:4-5), the paragraph ends a new one begins. It is possible that the first paragraph occurred before the war with Midyan, with Gad and R’uvein asking for the territory conquered from Sichon and Og right away because they wanted to avoid schlepping everything back and forth from the eastern side of the Jordan to the western side and then back again to the eastern side. Moshe didn’t say yes, and the conversation ended. Then, after the war, when the other Tribes getting cattle caused Gad and R’uvein to be concerned about losing their rightful territory, they approached Moshe a second time. Although the Torah put both conversations together in order to keep the narrative contiguous (just as the Torah may have included Yisro’s leaving in the same narrative as his arrival even if it happened much later, see Ramban on Sh’mos 18:1), the first paragraph may have occurred before the war with Midyan while the second paragraph occurred after the Tribes divided up the spoils, a development that Gad and R’uvein were afraid could impact which land they would receive.