Campaign of the Hills

The Campaign of the Hills (Campaña de las Cordilleras) was the last campaign of the Paraguayan War, lasting from July 1869 to the end of the war on March 1, 1870. The Paraguayans were completely defeated by the Allies. Brazilian writer Alfredo d'Escragnolle Taunay, Viscount of Taunay took part in the campaign and later wrote about it. At least 5,000 Paraguayans were killed during this campaign.

Background
After the occupation of the Paraguayan capital, Asuncion, by the allies, Marshal Luis Alves de Lima e Silva, Duke of Caxias considered the Paraguayan War to be ended with Allied victory. Since Paraguayan President Lopez refused to surrender, the Allies installed Cirilo Antonio Rivarola, a political opponent of Lopez, as temporary President in occupied Asuncion, and decided to continue the war. Lopez decided to resist in Allies in the mountainous region of Northeastern Paraguay.

Battle of Piribebuy
The Allied attack on the town of Piribebuy, then serving as a temporary capital for the Paraguayan government, lasted 5 hours, ending with the capture of the town and destruction of its official records

Battle of Acosta Ñu
The last major battle, in which Bernardino Caballero (who later became President of Paraguay) fought a Brazilian-Argentine combined force of 20,000 under Emperor Pedro II's son-in-law Prince Gaston and future Brazilian president Manoel Deodoro da Fonseca.

Battle of Cerro Corá
The last battle of the campaign was at Cerro Corá, in which a Brazilian force of 4,000 wiped out President Lopez's personal guard of 100-250 soldiers, killing Lopez, Vice President Sanchez and Lopez's son Juan Francisco.