In 1915, the Baltimore Terrapins, a team in the smaller and younger Federal League, sued the American and National baseball leagues for unfair practices in violation of the Sherman Anti-Trust Act. The legislation, passed in 1890, was meant to curb monopolies in inter-state commerce. The case languished in the courts (some say the doing of D.C. District Judge and Chicago Cubs fanatic Kenesaw Mountain Landis), and by the end of the year the league was finished, unable to weather the low war-time turnout.
“To repeat the illustrations given by the Court below, a firm of lawyers sending out a member to argue a case, or the Chautauqua lecture bureau sending out lecturers, does not engage in such commerce because the lawyer or lecturer goes to another State.”
To date, Major League baseball is the only professional sport in the U.S. that remains exempt from anti-trust laws, still enjoying the legal status of an all-American pastime rather than a powerful industry.