I think Tosfos tells us that we don't date Gittin today according to the year of the king's rule because no nation writes dates like this anymore. This is difficult for me because in Japan we do- it is now Heisei 20, the 20th year of Emperor Heisei's reign. Any official document is dated by the year of the emperor's rule, not the "Western date". We don't have a Beis Din here and I don't know of any gittin here, but would a Get it Japan be dated according to year of the king's reign, or would it be dated from the creation of the world? Would Tosfos's "psak" apply?
Surely there are other countries also with the same issue.
Daniel Moskovich, Kyoto, Japan
The Gemara (Gitin 80a) says that we date our Gitin according to the year of the local monarch because of Shalom Malchus. That is, if we don't use the local system for dating documents based on the year of the monarch's reign, we will engender enmity from the local population who will say that we have no respect for the king. The Rambam (Hilchos Gitin 1:27) says that today we date all of are Gitin according to the Jewish calendar (counting from Beri'as ha'Olam) or according to the Malchus of Alexander the Great. The Haga'os Maimoniyos, commenting on this Rambam, explains that we can date the Get according to Beri'as ha'Olam because the local population will not hold it against us if we use the year of the reign of the King of the world instead of their king. According to this reasoning, even if a country today - like Japan - uses the year of the reign of their king, the Get should be Kosher if it is dated according to the Jewish calendar.
Kol Tuv,
Yonasan Sigler