Introduction

During most part of the 1800s Argentina was far from being a true union. Although the country declared itself independent of Spain in 1810 it took decades before a true unity was set in Argentina. The first constitution, enacted in 1819, created the legal framework for a unitary country. Buenos Aires as a "master key" to the livestock exports, was chosen as federal capital of the new-born country. That meant that powers would center in the capital city. This led to the opposition of the provinces. Soon,a bloody fight between Unitarians and Federals emerged, dominating the political scene during the first years of the young country.

It does not mean that no attempt to achieve peace was made. In fact, by 1826 a meeting took place in Buenos Aires in order to establish peace between the two differents groups. A new constitution was written and Bernardino Rivadavia was elected president. Nevertheless, the provinces did not accept the goverment. As a result, Rivadavia resigned and civil war ensued from 1826-1828.

A significant step toward peace was given when Juan Manuel Rosas was appointed as president of Argentina in 1829. Rosas, a rich lanholder identified with the interests of the provinces, made great efforts to benefit commerce and education. In 1832 he left office and joined the fight in the south against tribes which did not accept the spanish presence since the colonial period.

Meanwhile, Argentina fell again in a vaccum of power. Neither the centralists (who favoured a strong central power in the hands of Buenos Aires) nor the federalists (for provinces supremacy in the confederation) could bring stability to the nation.

Being sufficient popular, Rosas was called to presidency again in 1835. At first, the federalists though they would have the old comrade in office once more. This time, however, Rosas' government would be far different.

Vice-Admiral John Pascoe Grenfell, commander of the Imperial Navy squadron during the campaign against Buenos Aires president

Rosas centered power in Buenos Aires, putting aside the provinces landowners. Some of them would never excuse the president for such treatment.

The relations with surrounding countries  were not free of problems. For some, Rosas never gave up of Uruguay as an Argentinean province. In 1839 he intervened in the internal strife between Blancos (Conservatives) and Colorados (Liberals), fauvoring the former ones with supplies and shelter.He also helped Manuel Oribe, leader of the Blanco Party, to besiege Montevideo (Uruguay's capital) in 1843. Acting so, he atracted the anger of the Colorados and the concern of the Brazilian Empire of an Argentinean hegemony on La Plata Region.

Thus, when in 1851 the provinces of Corrientes and Entre Rios raised an army to overthrow Rosas, led by Justo Jose Urquiza, Brazil and the Colorados joined in an alliance with him. Their first aim was to release Montevideo from Oribe's forces and put Rosas' ally out of fight. In July, while the Imperial Fleet cut the communications between Rosas and his ally by taking control of La Plata river, Urquiza's troops entered Uruguay. On September the 6th. the Imperial Army crossed the border ending Oribe's hope of a escaping route.

The situation in Uruguay: In Blue Urquiza's forces, in Red, Oribe's

Surrounded by overwhelming enemies, Oribe surrended after little  fight on October the 8th. From this point, Urquiza's eyes turned to Buenos Aires where he belived  a hard task  awaited for him.

Towards Caseros