A seemingly intrinsic part of the game of baseball is the keeping of statistics on the achievements of the players. Started by Henry Chadwick in the 19th century who devised the concept of batting average based on his experience of cricket. Commonly used statistics are explained here:
... was established under the Peace of Westphalia, in 1648, but political difficulties at the end of the 17th century almost eliminated them. In the 19th century, by state ...