Fernández, also known as Mataojo is a small populated centre in the eastern part of the Salto Department of northwestern Uruguay.

It is situated on the south bank of stream Arroyo Mataojo Chico, about 22 kilometres (14 mi) east-southeast of its confluence with Arapey Grande River.

One of the last massacres of the Charrúas, by a force led by Bernabé Rivera, happened in the area of Mataojo on 17 August 1831.

In January 1832, he was sent across the Atlantic as a living specimen for the Academy of Sciences of Paris.

Due to disagreements of various officials, however, he had to remain on board the L’Emulatión, the ship that carried him, until his death in October of that year.