Furious, Bolivar resolved to declare war against Peru on June 3, 1828, with former president of Bolivia Antonio Jose de Sucre being appointed Commander of the Colombian Army.

The Peruvian Navy immediately proceeded to occupy and establish blockades along the Gran Colombia coasts, winning the first confrontation in the Battle of Punta Malpelo, forcing the Colombians to retreat.

In the land, the ties were more balanced, with the outnumbered Peruvian Army seizing the city of Cuenca on the Battle of Saraguro on February 13, 1829, and pushing north near Guayaquil.

The conflict originated due to the international debt Ecuador, as the Gran Colombia, had to take from European creditors, mainly British, after the war of independence from Spain.

Wanting to find a source of income, finances minister Francisco de Paula gave the creditors rights to several territories in the forest, some of them over disputed lands with Peru.

Thus, on October 26, 1858, the Peruvian congress authorized president Ramón Castilla to command and army against Ecuador if needed to secure the national territory against European creditors.

By this time, Ecuador was facing an internal crisis, called by Ecuadorian history books as the “Terrible Year”, in which a number of different politicians were fighting for control of the country as its coasts were in the middle of a blockade.

The incompetence of the government and military was so great during the War of the Pacific period that it led to an intellectual movement dedicated to restoring pride for Peru, creating modern Peruvian nationalism.

[10] In addition, the 1962 Peruvian general election saw the rise of the American Popular Revolutionary Alliance, with the armed forces and traditional aristocrats viewing their platform of land reform and the political inclusion of the indigenous peoples of Peru as a threat.

[17][18] Vargas Llosa later reported that Ambassador Quainton, personally told him that allegedly leaked documents of the Central Intelligence Agency (CIA) purportedly being supportive of the candidacy of his opponent, Alberto Fujimori, were authentic,[19] with Rendón writing that the United States supported Fujimori because of his relationship with Vladimiro Montesinos, who had previously been charged with spying on the Peruvian armed forces for the CIA.

[23] During this time, the armed forces' Grupo Colina death squad would kill dozens during various massacres in Peru and the military would participate in the Cenepa War against Ecuador in 1995.

Following the downfall of Fujimori and Montesinos, the use of the terruqueo in the beginning of the twenty-first century was used to influence the public instead of violence performed by the military, though its use would provide impunity to members of the armed forces who violently responded to protests in the nation.

[29][30] The Joint Command of the Armed Forces is tasked with the mission to "plan, prepare, coordinate and conduct military operations and actions to guarantee independence, sovereignty and territorial integrity and support the national development of Peru".

[31] This branch of the armed forces was developed in the 1950s following World War II, when Peru evaluated operational tactics used and adapted them to their own military.

[33] The Peruvian Navy (Marina de Guerra del Perú) is organized in five naval zones headquartered in Piura, Lima, Arequipa, Iquitos and Pucallpa.

The Peruvian Air Force is divided into six wing areas, headquartered in Piura, Chiclayo, Lima, Arequipa, Rioja and Iquitos.