[2] During his political life, de Achá became Minister of War during the presidency of José María Linares, whom he overthrew on 14 January 1861, by means of a coup d'état.

[2] As soon as he entered the Palacio Quemado, de Achá declared a general amnesty on 6 May 1861, for all the politically persecuted who were outside the republic, in addition to cutting off the legal proceedings against them.

[4] On 23 May 1861, de Acha also decreed the delivery of per diems and allowances (economic remuneration) to the deputies of the assembly in the amount of about 200 pesos per month that the departmental treasuries should pay.

On 13 July, authorization was decreed to create a commission to repatriate to Bolivia the remains of General and former President José Ballivián, which were still in Rio de Janeiro, Brazil.

When the government in Potosí was informed of what had happened, on 5 October 1861, it ordered that all the detainees, soldiers and civilians, be tried by an ordinary war council and decreed a state of siege in the provinces of Pacajes and Ingavi and in the district of La Paz.

[2] After this alleged armed uprising against the government, Yáñez ordered the prison guards to assassinate Jorge Córdova with four shots from a firearm in retaliation and punishment.

[5] Between 2:00 and 4:00 in the morning, Yáñez and his personal guard, including the sentinel soldiers of Loreto, hurriedly took all the prisoners out of their cells, taking them to the middle of the Plaza Murillo, and shot them.

Once President José María de Achá found out about what had happened, he remained impassive and neutral without carrying out any punishment against Plácido Yáñez.

[8] Several years had passed since the Chileans had initiated a brazen expansionist policy on Bolivian territory (Atacama), whose riches in guano and saltpeter they coveted.

But the continental defense against the aggression of the Spanish Pacific fleet in 1864 left this problem in the background, and Bolivia joined the quadruple alliance against Spain, along with Peru, Chile and Ecuador.

[7] Aware of the Chilean threat, he arranged a loan with Great Britain to build a railway to the coast and buy warships to defend the coastline.

The processing of this project was entrusted to the industrialist Avelino Aramayo; but when everything was ready, he was frustrated by the refusal of the finance minister, Miguel María de Aguirre.

[7] Despite his military talent and leadership skills, de Achá was unable to successfully confront the uprising of his former collaborator and protégé, Mariano Melgarejo, who overthrew him on 28 December 1864.

[citation needed] After a couple of years in exile, the broken and unpopular de Achá returned to Bolivia, where his safety was guaranteed by the now consolidated regime of General Melgarejo.