“MONSTROUS AND ILLEGAL PROCEEDINGS”: LAW ...

province within the national framework. The impending end of Urquiza’s six-year term as
the Confederation’s president further destabilized the personal coalitions sustaining the
fragile political unity in the interior. In March of 1860, Santiago Derqui was elected the
Confederation’s second president. Urquiza continued, however, to hold sway over much of
the Confederation through his personal power and associations. Desperate to carve out an
independent political base, Derqui began to court elements within the Confederation that
opposed Urquiza’s concessions to Buenos Aires.
As Mitre, Urquiza and Derqui all maneuvered to control power within the new
national alignment, local tensions sparked another explosion of violence. This time a
conflict between pro-Mitrista forces and the Derqui-allied governor, José Antonio Virasoro,
in San Juan province touched off events in late 1860. In November, forces led by Antonio
Aberastain assassinated Virasoro and seized power. Derqui responded by brutally crushing
the uprising. He ordered the execution of Aberastain and many of his followers. Outraged,
elites in Buenos Aires broke off negotiations with the Confederation over reunification. The
two sides rapidly moved towards war. 191
Urquiza reluctantly took to the field again in an effort to preserve the fragile union
between Buenos Aires and the interior. He marched south and met Mitre’s forces along the
Pavón River on 17 September 1861. The fighting produced no clear winner. The battle’s
aftermath did. Urquiza elected to withdraw from the field and retreat back to Entre Ríos.
The federalist commander then refused pleas from Derqui’s government to resume the
campaign. Instead, Urquiza now began to work with Mitre in an effort to strike a grand
compromise between provincial autonomy and national consolidation. Urquiza hoped to
exchange loyalty to Mitre’s new national framework for the continuing right to control
191 Scobie, La Lucha por la Consolidación, 301-17.
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