He was notable for being one of the main general who sided with Bartolomé Mitre during the Revolution of 1874 [es] but when he was arrested he was discharged and after being pardoned, he was reincorporated into the Argentine Army in 1877.

1857) and his Portuguese-Brazilian wife Ignacia Graces (b. Captaincy of Rio Grande de San Pedro, ca.

[1][2][6] Rivas enlisted as a cadet as a defender of the Great Siege of Montevideo during the Uruguayan Civil War and became a personal friend of Bartolomé Mitre.

He served on the border with the Argentine Confederation and seconded Manuel Hornos during the Battle of El Tala on November 8, 1854, repelling the invasion of Hilario Lagos.

He returned to Fort Cruz de Guerra where he repelled a Native American attack from Calfucurá who helped the Federalists in their attempt to control the south of the province, advanced to the Chico Stream that crosses the San Juan ranch, where they were finally repulsed.

He pursued the montoneros throughout La Rioja and San Luis, and defeated them in the battles of Las Mulitas and Los Gigantes.

He then signed the Treaty of La Banderita with him through which the submission of Chacho and his men was negotiated in exchange for an amnesty for all the montoneros.

In the middle of 1870, he went to Entre Ríos Province to crush the uprising of the last Federalist leader, Ricardo López Jordán as head of the departments on the coast of the Uruguay River.

In March 1872, Lonco Calfucurá led a large army of Native Americans into Christian territory again but he made the critical error of facing the forces that came out to pursue him in open field and in general battle.

By order of Mitre, they headed towards the north of the province, but on their way, they encountered the entrenched forces of Colonel José Inocencio Arias at the ranch of La Verde and were completely defeated on November 26.

He was reinstated in the army in 1877 but wouldn't be given any commands as the General Staff considered him dangerous which resulted in his absence from the later years of the Campaign of the Desert.