1912 in Argentine football saw the division of Argentine football into two rival associations, when Federación Argentina de Football (FAF) was established to organise its own championships. Thus, Quilmes won the official AFA tournament, while Porteño won the FAF title.

Many former players of Alumni (dissolved one year later) went to play for Quilmes, which would be the champion. The tournament had no relegations.

In July 1912, Gimnasia y Esgrima de Buenos Aires disaffiliated from Asociación Argentina de Football, founding the Federación Argentina de Football (FAF) presided by Ricardo Aldao. Recently promoted teams Porteño and Estudiantes (LP) joined the new league, among other clubs.

1912 was the inaugural season of the dissident FAF league. This tournament was formed by 3 dissident teams from the Asociación Argentina (AAF): Estudiantes de La Plata, Gimnasia y Esgrima (BA) and Porteño, plus the 4 teams promoted from the second division: Argentino de Quilmes, Atlanta, Independiente and Kimberley (Villa Devoto). The last club added was the recently created Sociedad Sportiva Argentina.

Independiente and Porteño finished level on points at the top of the table, necessitating a championship playoff. The game was suspended at 87' after the Independiente players abandoned the pitch in protest at a disallowed goal by referee Carlos Aertz. The championship was then awarded to Porteño.

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