parshanut torah comment - "The Romans' Book" in Ramba"n

The commentary of Ramba"n on Vayikra 26:16 explains a large swath of parashas B'chukosai as an allegory to the two batei Mikdash and the corresponding exiles. Included therein, he elaborates on the warring and exiling protocols of the Roman Empire, citing as corroborative proof "The Romans' book".

וכן כתוב בספר הרומיים...

Is there a specific book to which he is referring or is it simply pointing the skeptical reader to check the original documentation of the Romans' own if he needs more proof to Ramba"n's contention?

Answer

In the Torah periodical ישורון for Kislev 5767, in an article on "Derashat haRamban - Torat Hashem Temimah", on page 38-9 (and specifically in footnote 14) Rav Yaakov Yehuda Zilberlicht discusses what Ramban is referring to by ספר הרומאים (The Book of the Romans). Possibilities that he raises:

• It is obvious that Ramban is referring to a Roman history book, the question is: which one?


• הגר"י ספרקה (Rav Y. Spraka?) in his commentary "Chazon haGeulah on Sefer haGeula) says that this is referring to Josephus. Especially because it records a parallel event there. Also Rav Chadah in his commentary on Ramban.


• General Roman history books (and not Josephus) - since Ramban makes specific reference to Josephus in a different place, if he wanted to refer to it by name, he would have. Also, there are many other places in Ramban where he refers to "Sifrei X" - "the books of X", X being the name of other nation (Casdeans, Egyptions, Umat Tzava, etc), so there is precedent for Ramban referring to history books of some non-Jewish nation in this way.