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The 1909 Italian Football Championship season was won by Pro Vercelli.
In this season, as in the previous one, two championships of Prima Categoria were played:
Federal Championship, the first tournament where foreign players (if they lived in Italy) were also allowed to play; the winners would be proclaimed Campioni Federali (Federal Champions)
Italian Championship, the second tournament where only Italian players were allowed to play; the winners would be proclaimed Campioni Italiani (Italian Champions)
The winner of Federal Championship was Pro Vercelli. They won as a prize Coppa Oberti.
The winner of Italian Championship was Juventus. They won as a prize Coppa Buni.
However, the "spurious international teams" (the clubs composed mostly of foreign players), adversing the autarchical policy of the FIF, decided to withdraw from Italian Championship in order to make the Federal competition the most relevant tournament and to diminish the Italian one. More, Pro Vercelli's victory of the Federal Championship (where Juventus was soon eliminated) with an all-Italian squad transformed the Italian Championship into a meaningless tournament. The dissenters' strategy worked out: the failure of the Italian Championship won by Juventus forced the Federation to later recognized the Federal Champions of Pro Vercelli as "Campioni d'Italia 1909", disavowing the other tournament.
Almanacco Illustrato del Calcio - La Storia 1898-2004, Panini Edizioni, Modena, September 2005
Carlo Chiesa, La grande storia del calcio italiano Chapter 2: Juve, scippati due titoli! Inter, l'atroce beffa (1908-1910), pp. 17–32, Guerin Sportivo #5, May 2012.
Digitalized online archive of Turin newspaper La Stampa.