Jack Marston is the secondary protagonist of Red Dead Redemption, but much of his character and his ultimate fate is cloaked in mystery. This appears to be a deliberate choice, as Red Dead Redemption is a game about things – and people – vanishing into history as time marches on. However, one fan recently noticed something interesting about Jack in the game's instruction booklet.

According to the booklet, Jack Marston's proper name is John Marston, Jr, named after his father John Marston – though he isn't often referred to as such. This revelation caused some confusion among players, especially those unfamiliar with American nicknaming conventions.

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During the time period that the Red Dead Redemption games take place in, Jack was a common nickname for John, despite the two names being the same length. Now, Jack is often treated as a separate name entirely, though some Johns still choose to go by Jack. Other names with similar origins include Hank and Harry, both of which are nicknames for Henry, and Molly, which is a nickname for Margaret. While there are creepier Easter eggs in Red Dead Redemption, this is an interesting window into the past.

Jack has also historically been used as a general colloquial nickname for men in general, dating back to about 1,200 AD as a generic name for peasants. Over time, it worked its way into many English words like lumberjack and steeplejack, as well as phrases like "don't know jack." Jack Marston may have chosen to go by the nickname through most of his life to avoid confusion with his father, though it's uncertain why he kept the nickname even after his father's death. It could well have something to do with the trauma that Jack Marston is clearly grappling with during the epilogue of Red Dead Redemption.

While the initial post was met with a lot of good-natured joking about English nicknaming conventions--the old joke that Bill is short for Billiam showed up more than once in the comment section--some posters were kind enough to explain the whole thing to fans who may not be native English speakers, or who simply don't know the history of Jack.

Several users shared anecdotes about people they knew who went by Jack or stories from American and English history. One poster even theorized that Abigail named Jack to solidify the paternal connection between him and John Martson, Sr, which is questioned in Red Dead Redemption 2. Of course, the connections between Red Dead Redemption and Red Dead Redemption 2 can be murky and ambiguous, but the point remains that players are still technically playing as a John Marston throughout the first game.

Red Dead Redemption is out now for PS3 and Xbox 360.

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