Want a history job? Try this industry...
If you can get a content-based job in the travel industry -- whether as a writer, proofreader, graphic designer, or whatever -- it may open up opportunities for you to delve into history. How do I know? Because I've done it firsthand.
In my last two jobs -- both for hotel start-ups -- I was tasked with writing hotel descriptions and other travel pieces that at times allowed me to research historic hotels, destinations, monuments and museums, etc. Many travelers enjoy visiting historic sites, so it's no surprise that hotels, cruise/air lines, and other travel niches try to sell "history" in their marketing communications.
There was a trade-off, though. I had the flexibility to write about this mentally-engaging stuff, but at the expense of being paid poorly. I was laid off from the first job during the throes of the recession and left the second one for a marketing job in the timeshare industry. While my current job pays a lot better, I don't get to write history-based content anymore; it focuses solely on travel products and services.
If you can find a content-related job for a hotel company (e.g., a third party service like Expedia or Trivago), you might have the chance to write about historic hotels and the historic attractions near them. These jobs aren't easy to find, however. I would know because I'm currently in search of one like this.