Should I minor in history with a linguistics major?

I will assume that you’ve already been read the riot act about the impossibility of getting an academic position, the need to step on corpses and network, and the imperative to do something fashionable (which historical linguistics is not) in order to get hired.

Why yes, I am jaundiced. Why do you ask? (Nick Nicholas’ answer to What is your personal experience with obtaining a linguistics degree?)

A history minor is not vital. If you’re doing historical linguistics for languages with well-defined histories, like most of the Indo-European languages… well, that’s even less likely to make you employable. For languages without detailed historical records (or without records from the time when the changes were happening, which is pretty commonplace), there’s not much to learn from history anyway: you may end up providing historians with more information than they provide you.

At any rate, you need some level of understanding of historical changes to contextualise language; but I’m not convinced you need much more than an intelligent layperson can get out of Wikipedia. For a lot of historical linguistics, anthropology would be a more useful adjunct to get formal training in than history.

But do read those Wikipedia pages. Linguists can get pretty bone-headed when trying to do history. Just like computer scientists, when they try to do historical linguistics.