It's always fun to unearth some esoteric piece of personal finance history. I know there are only a few nerds out there who care (hello, Grant Sabatier!), but those of us who care really care.
Two years ago, I published an article exploring the history of financial independence in which I noted that the earliest reference I can find to the notion of financial independence comes from an 1872 book called Money and How to Make It by H. L. Reade. And it wasn't until the 1950s that the concept of early retirement (at least in the sense we mean it today) gained traction. But despite my research, I still have questions, such as: What's the source of the modern FIRE movement?
Recently at The Retire Early Home Page — a site so old that it existed (and still exists) at the dawn of the web — John P. Greaney answered the question: Who coined the term FIRE?