[william_9]

This is recalled off the top of my head from a bit of research a few years ago. Please excuse the shorthand as the dates and timing of the series are foggy in my memory.

The quick story is the Cubs and White Sox used to play each other in an exhibition series to crown a "Champion of Chicago". The Cubs won in 1905 and were reigning champions for the 1906 season. Hence the pin and the stationary. It has nothing to do with the World Series or League championships, just the city, and primarily for bragging rights.

True bragging rights for 1906 belonged to the White Sox who went on to win the World Series by defeating the Cubs in 1906. That victory gave the White Sox claim to "world champions" for the 1907 season.