Baseball, according to historians, has been around since at the 1800s. The game became more standardized in 1845, when Alexander Cartwright invented the baseball bat and developed a set of rules for the game.
Boston has a long history of baseball, which extends back to a time before the Red Sox! (Yes, there was a time before the Red Sox!) One of the earlier Boston teams was the Beaneaters, and, in 1897, they battled it out with the Orioles for the Pennant. The story of the fierce rivalry is chronicled in a book we just added to the collection, A Game of Brawl: The Orioles, the Beaneaters and the Battle for the 1897 Pennant by Bill Felber [796.357 FEL]. The author has a website that has photos of the teams and some of the other characters who made the 1897 season a memorable one.
We also have The Boston Braves 1871-1953 by Harold Kaese [796.357 KAE]. The Braves were originally the Boston Red Stockings, but by 1953 they bailed and headed out to Wisconsin to become the Milwaukee Braves.
For some more early baseball history, borrow the first two episodes ("Inning One: Our Game" and "Inning Two: Something Like a War") of Baseball by Ken Burns [796.357 BUR].
And, for a look at the evolution of baseball rules, we have The Rules of Baseball: An Anecdotal Look at the Rules of Baseball and How They Came to Be by David Nemec [796.357 NEM].