I realize many of you don't know what historians DO. Don’t feel bad; most people don't. Nor should they. If I were reading a blog about, say, civil engineering or radial oncology, I'd need some basic background because I have NO idea what civil engineers and radial oncologists do. I mean I know that engineers build dams and bridges, but that’s the beginning, middle, and end of what I know.
So, I thought I'd provide some basic background on how historians work. If you're a historian or professional researcher, you can skip this part.
Much of my daily routine consists of doing research. I conduct that research using two kinds of material -- or, as historians say: "sources" -- primary and secondary materials (or "sources).
An example of primary materials, or, "primary sources" are letters written by Abraham Lincoln to his wife, Mary Todd Lincoln. A secondary source is a book or essay in which a scholar (a historian) analyzes those letters.
So, for example, when I decided to write a history of Key West, Florida, I needed to learn about Ernest Hemingway, who lived in Key West for many years. To research his life, I used primary sources such as letters that Hemingway wrote to his friends and family while living in Key West.
I also relied on secondary sources, namely biographies of Ernest Hemingway. The letters (primary sources) provided Hemingway's first-hand accounts of Key West. The biographies (secondary sources) provided details of Hemingway’s life (his childhood in Illinois, his years in Paris, etc.)
So when I'm writing a book, whether it's a history of Key West, of beer in America, or (my current project) a history of meat, I read a wide range of material. Lots of material. What feels like an endless river of material.
And once I've finished the research, then I have to write the book. (Which, I might add, is a quite different task that requires a different set of skills.) Which is why I only publish a book every few years. Ain't no way to speed up the process.