The admirers of the game in St. Louis, Mo., are taking about getting up a reliable baseball ten to represent St. Louis in the contest for the professional pennant of 1874. They do not relish the idea of Chicago having a club and getting a chance of winning the championship, while St. Louis has to look on without participating in the fight. A well-managed professional ten in St. Louis would not only pass as a stock investment, but it would greatly add to the interest of the game in that section of the country. We hope the St. Louis gentlemen will not allow Chicago to be the only representative in the arena from the West next season. Ten fine players could be had at very moderate salaries now. Let a club be started at once.
-Mears Baseball Scrapbook, Volume 4, 1856-1907
And that last bit is a distinction I'd like to make. The 1875 season in St. Louis is remembered as the first season of professional baseball in the city but there were professional clubs in St. Louis prior to that. While there is no smoking gun, there are plenty of hints that the amateur St. Louis clubs were compensating their players as early as 1867. I have no doubt that the Empires, Unions, Reds and other St. Louis clubs were compensating their players in one form or another during the Pioneer era and that you had professional players and professional clubs, in the modern sense of the word, prior to the 1875 Brown Stockings and Red Stockings.
Also, it should be noted, while Chadwick was happy to take credit for the idea of a professional club in St. Louis, the real impetus for the creation of the Brown Stockings came from Chicago and the success that the White Stockings had against St. Louis clubs in 1874. I'll touch on that tomorrow.