# Oribe defeats Rivera at Arroyo Grande (6 December 1842)

URL: https://allhistories.com/uruguay/timeline/1842-oribe-defeats-rivera-at-arroyo-grande
Location: Arroyo Grande, Entre Rios, Argentina
Themes: battle

On 6 December 1842 Manuel Oribe's army beat Fructuoso Rivera at Arroyo Grande in Entre Rios, in present-day Argentina. The Blanco side fielded about 12,000 men against roughly 7,500 Colorados. Rivera lost about 2,000 killed and 1,400 wounded, while Blanco losses were far lighter. The Colorado army had crossed the Uruguay river hoping to carry the war into Argentina, but Oribe, with Argentine federal troops, destroyed it. Rivera escaped with a few followers. The scale of the Colorado defeat left Montevideo without a field army and forced the government to rely on the city walls and foreign volunteers. Arroyo Grande was the largest battle of the Guerra Grande. Its direct result was the Blanco march on Montevideo and the start of the Great Siege. It also shows how closely Uruguayan factions were tied to Argentine ones, since the fighting took place on Argentine soil with Argentine units on both sides.

## Why it matters
It was the largest battle of the Guerra Grande and led straight to the siege of Montevideo.

Ruler at the Time: [Fructuoso Rivera (1839–1843)](https://allhistories.com/uruguay/rulers/fructuoso-rivera-second-term)

## Sources
- [Battle of Arroyo Grande](https://en.wikipedia.org/wiki/Battle_of_Arroyo_Grande)
- [9.htm](https://countrystudies.us/uruguay/9.htm)
- [History of Uruguay](https://en.wikipedia.org/wiki/History_of_Uruguay)