An interesting comment on studying pirates, from /r/AskHistorians:

"Pirate questions are often difficult, because pirates as a group have been so heavily fictionalized -- and were often fictionalized even in the "golden age" of piracy (or shortly thereafter) -- that it becomes hard to separate reality from fiction. Indeed, there is evidence that later sailing crews, including pirates, took on behaviors that they may have read or heard that "pirates" did -- even if these accounts were fictional, meaning that fictional accounts of pirate activities actually became reality due to people acting out what they'd seen in fiction." https://www.reddit.com/r/AskHistorians/comments/60deda/how_h...