General Rosas and his gauchos had gone…

General Rosas and his gauchos had gone on the offensive against the centralists after the Argentinian federalists toppled the Dorrego government,

Rosas, who in 1820 had defeated the European expeditionary forces with the help of gauchos, had come on to the national scene as a powerful cattle rancher.

He controls the cattle frontier pampas of Argentina, allowing him to rule over the capital, Buenos Aires.

Championing the autonomy of the federation's constituent states, Rosas leads his gaucho militia against the insurgent centralist Unitarians.

López now joins forces with Rosas to defeat Lavalle in Puente de Márquez on April 26, 1829.

After Rosas makes peace with Lavalle without López's consent, however, the relationship between the allies is strained.