Federal League
 

Anyone who's tried it knows that "Add Historical Major League" only produces the National and American Leagues (as subleagues of Major League YYYY).

I'm sure we all are aware that in 1914 and 1915 there was a "third major," the Federal League. (On a scale of major-league legitimacy, I rank it equally with the 1890 Players League, above the 1870s National Association, and way, way above the 1884 Union Association.)

(EDIT: The Lahman does include stats from all these leagues. I just checked.)

(EDIT: I've done bit more research on the FL. Turns out it did exist for the 1913 season as well, but did not attain "major" status until '14, similarly to the American League of 1900-'01.)

Is there a relatively simple method of using a Lahman-type database to generate a historical NL/AL and a concurrent FL, for these years?

Good question. I've never been able to do it.

The way I did it was to edit the teams.csv file and change all LgID for the 1914 Federal league teams to either "AL" or "NL". I then imported 1914 as a historical league, and created another fictional league. Once everything is imported the 1914 Federal League teams should be in the AL and NL. You can then move them to the fictional league.

I am currently running (or have been setting up) a hypothetical historical league starting in 1914. In subleague 1, I have the FL teams. Subleague 2 has two divisions: the AL and the NL. I had a draft rather than deal with placing players on the correct teams, but you could do that, since it imports them all. Or you could have done what Pyroman did.

What's interesting is that for some reason, with this setup, only the AL and NL have playoffs, so it works out pretty well. The FL doesn't participate.

I'm planning on playing out history as if the FL was successful. The AL and NL are combined into the UL (United League). I'll eventually move teams around to even things out and to stop too many cities from having multiple teams.