[1] The origins of the flag date back to 1815, when José Gervasio Artigas created it for an alliance of six provinces known as the League of Free Peoples.

The final design was not created directly by Artigas but by José María de Roo, a customs official from Montevideo and an expert in heraldry.

[2] After the fall of the League following the Portuguese invasion of Banda Oriental, the flag continued to be used on the west side of the Uruguay River by Santa Fe and Entre Ríos.

The republic came to an end a year later when, during the campaign in Santa Fe, Ramírez was betrayed by one of his commanders, Lucio Norberto Mansilla, and then killed after being captured by López's troops.

However, a year later, the province was placed under the direct administration of the president of the Argentine Confederation, and the flag was abandoned.

The reason was that Urquiza became president, and since Buenos Aires was under the control of the Unitary Party, the capital of the Confederation was temporarily moved to Paraná.

9385/02, passed on 17 January 2002 added details regarding the colors of the flag, specifying that the red shade of the diagonal stripe should be "intense".

The flag was declared a mandatory symbol in patriotic ceremonies, civic and institutional events in the province.