What the antagonists did he cared little, so long as they enfeebled the country and increased his chances of dominating it.

At length, in 1845, the two European powers established a blockade of Argentine ports, which was not lifted until the dictator grudgingly agreed to withdraw his troops from the neighboring republic.
More than any other single factor, this intervention of France and Great Britain administered a blow to Rosas from which he could not recover.
The operations of their fleets and the resistance of Montevideo had lowered the prestige of the dictator and had raised the hopes of the Unitaries that a last desperate effort might shake off his hated control.

In May, 1851, Justo Jose de Urquiza, one of his most trusted lieutenants, declared the independence of his own province and called upon the others to rise against the tyrant.

Enlisting the support of Brazil, Uruguay, and Paraguay, he assembled a "great army of liberation," composed of about twenty-five thousand men, at whose head he marched to meet the redoubtable Rosas.

On February 3,1852, at a spot near Buenos Aires, the man of might who, like his contemporary Francia in Paraguay, had held the Argentine Confederation in thralldom for so many years, went down to final defeat.