Answer by Tom Harrison
This is a question that I once worried about a lot! The short answer is that there is no clear evidence that he understood or spoke any language other than Greek. People have tried to argue that he must have spoken Aramaic, on the basis that it was used widely for administration in the Persian empire, and so he must have known it… but there simply isn’t any positive evidence of this. A better case can be made that he would have spoken Carian. Halicarnassus was a mixed Carian-Greek city. Herodotus’ father had a Carian name, Lyxes. And there have been a number of inscriptions written in Carian found in Halicarnassus. So it’s been argued, very reasonably, that growing up in this environment he would have mingled with and understood Carian speakers. But whether he spoke Carian or not probably doesn’t have a big impact on how we understand his work. He only refers to the Carian language three times, perhaps because he just took it for granted.
Herodotus does show more excitement about other foreign languages! He includes lots of foreign words (especially Egyptian and Persian) in his Histories, and he seems to prize them. But most of the foreign words that he uses can also be found in other Greek authors such as Aeschylus, so it’s perhaps likely that he learnt them indirectly. He also at one point seems to give away the fact that he didn’t know Persian. He says that all Persian names end in the letter sigma (that’s in the Persian ethnography at 1.139), which probably reveals that he only knew them in their Greek forms. (Not everyone thinks that Herodotus was wrong, in fact: some would point out that there’s an important distinction between how Persian names were written and how they were pronounced, and Herodotus might have known more than we do.) He also seems to have a quite unrealistic idea of how interpreters might work (by comparison with Xenophon in his Anabasis, for example): would Darius really have been able to find interpreters who could handle both Greek and Callatian Indian, which is what Herodotus seems to imagine in a famous scene in Book 3 (3.38)?
So, it’s a very difficult question to give a straightforward answer to… Perhaps more interesting in the end than which languages he spoke is the question of how he understood foreign languages in a wider sense. How did he understand the relationship between languages? Was there a first language from which others were descended? If you want to know more about any of this, one first step would be to look at an article I wrote ages ago for the online journal Histos. If you have access to a University library, I’d also recommend an important book by Rosaria Munson: Black Doves Speak. Herodotus and the Languages of Barbarians (Cambridge, MA 2005). And (again, not accessible to everyone) I’ve recently discovered a really clever piece on Herodotus’ understanding of language by David Chamberlain (Arethusa 32.3 (1999) 263-312).