The allegory requires the removal and destruction of the “main branches.” Translating image to history, the main event of this part of the allegory is the destruction of Israel’s established power structure, after which “wild branches” are grafted in. This two-part process can be correlated to historical events, but not in ways that fit the allegory’s precise timetable. Again, allegories are general parallels, not retellings (or foretellings) of historical events.
Three historical episodes may be seen as parallels to the “destruction” of the main branches. The first is the Assyrian invasion and the deportation of the ten tribes in 722–721 B.C. The second is the Babylonian invasion of 586 B.C., and the third is the destruction of Jerusalem in A.D. 62. The destruction of the main branches suggests the first dispersal rather than the second, as the Assyrians “destroyed” not only the elites but also the mass of the Israelites by carrying them away. In the Babylonian conquest, the people were carried away, but returned, and our history is written by those survivors; thus, they do not fit the allegory on this point. The destruction by the Romans fits as a category, but its occurrence in the more distant future greatly reduces its effect on Zenos’s presumed audience.
The “grafting” of the wild branches might refer to intermarriage with Babylonians who might have entered Judah after the conquest, but there is no evidence that foreign populations were integrated into Jerusalem after the leadership had been removed. Hoskisson, however, suggests intermarriages as constituting “graftings” after both the Babylonian and Assyrian invasions.
Identifying which historical event corresponds to grafting depends more on allegory than on history. In the allegory, the grafting invigorated the root and, therefore, is a positive element. It is hard to imagine a scenario in which intercultural marriages would be considered beneficial to covenant Israel.
A better interpretation is that the Gentiles are adopted into the Abrahamic covenant, a reading which also parallels Paul’s allegory. The events following this verse in the allegory suggest that this latter interpretation is to be preferred. It would be particularly timely in the New World when Jacob records this allegory.