The War of the Pacific (1879-1883), also called the War of the Saltpeter, pitted the Republic of Chile against the alliance of Peru and Bolivia over rich saltpeter and nitrate deposits. [[note]]"Nitrate deposits" being a polite term for [[ Guano]], i.e. bird dung. Guano is rich in nitrate, which is needed to make modern fertilizer and explosives. So yes, it was totally worthwhile (at the time, but not anymore; for why, see below) to fight a major war over bird poop. And you thought it was just the annoying stuff that got stuck to the windshield of your car...[[/note]] The deposits were on Peruvian and Bolivian territory, and the Bolivian deposits were mostly mined by a Chilean company. Hilarión Daza, the President of Bolivia, tried to raise the taxes the Chileans paid (in violation of a treaty), and when they wouldn't pay he nationalized the company. Then Chile invaded Bolivia, and Peru (which had a mutual defense treaty with Bolivia) got dragged into the fight.

However, things were actually a bit more complicated. Over the years following the [[ChinchaIslandsWar War against Spain]] (Not to be confused with the War of Independence), Chile had been arming itself, gaining indirect support of the British, the Germans and the French, which were the one who sold the weapons and the ironclads to them, due to the desire of Chile's ruling class to seize control of the lands in the north, thus creating the tension between Chile and Bolivia, since at the time Bolivia controlled the strip of coast north of Chile.

After the situation between the Bolivian and Chilean governments started to go awry, Peru sent a diplomatic mission to try to resolve the problem peacefully, also hoping for time to properly arm itself in case a war started. Unfortunately, the countries supplying the weapons and ships (i.e. France, Germany, Britain) had already chosen a side, and were not willing to sell Peru anything. To make things worse, the diplomatic mission turned out to be a failure, for Chile was determined to go to war.

'''The Naval phase''':

Both Peru and Chile knew that, to first gain control of the land, they needed to secure dominion over the sea. To accomplish this, Miguel Grau was given command of the Peruvian armada, a decision that proved to be a smart move for the Peruvians. Grau, commanding only the monitor ''Huáscar'', was able to stall the Chileans for months, to the point that a coup overthrew the Chilean government in order to finally hunt down the damned ship, which they finally did in the ''Combate de Angamos'' (''Naval Battle of Angamos''), using '''six''' ironclads to capture the ''Huáscar''.

'''The Campaign of Tarapacá''':

With the ocean in their power, Chile began to manuever its army against the Peruvian-Bolivian one, which didn't have the proper weapons or equipment to make a good fight against Chile, to the point that they even asked the housewives of Lima to make uniforms out of bed sheets (which is why the Peruvian soldiers were sometimes depicted with white uniforms). As the battles went on, the territories of Tarapacá (Peru) and Antofagasta (Bolivia) were lost. Bolivia suffered an internal conflict, leaving the war and Peru alone against Chile.

'''The Battle of Arica''':

As the situation started to go badly for the forces of the Peruvian southern army, they made their stand on the hill of Arica. Colonel Francisco Bolognesi was given the choice by the Chilean command to surrender, but he knew that should they fail there, the whole southern front would be lost. Meanwhile, two batallions called the ''Infernales''[[note]] ''Hellish'' [[/note]] and ''Leiva'' were ready for battle, and would have joined his force . . . except that a man called Nicolas de Pierola gave them the order to not join the forces of the south, thus dooming the Bolognesi's army.

One of the most memorable moments of the battle was the sacrifice of Colonel Alfonso Ugarte, who threw himself and his horse off the hill and into the sea to prevent the national flag from falling into the hands of the Chileans, who at the time had the practice of burning the banners of their enemies. The other one, which is rather infamous, was the chilean ''repaso'', which was the act of killing those that survived by bayonet and the rape of the women of Arica.

'''The Campaign of Lima''':

After the battle of Arica, Peru tried to negotiate with Chile for a peace treaty, however, their demands were incredibly harsh towards Peru and negotiations failed. Now, Chile began to move its army north toward the Peruvian capital city of Lima, while a naval force called the ''Lynch Expedition'' attacked Peru's the northern coast. The army finally disembarked on the central coast of Peru and began to move towards the capital. Along the way, they burned and destroyed the Balneario of Chorrillos, finally ending in the battle of Miraflores, in which the last of the Milicia died, as well as the best of the peruvian youth (i.e. teenagers and young boy who were recruited to fight against the chilean invaders) and the army of Chile entered the capital.

'''The Final phase of the war''':

After the occupation of Lima, resistance carried on in the mountains and highlands of Peru, most notably the ''Warlock of the Andes'', General Andres Avelino Cáceres. However, it eventually died out due to differences between the Peruvian generals.

The Treaty of Ancón ended the war between Peru and Chile in 1883. In the treaty, Chile won the province of Tarapaca from Peru. Chile also occupied various other provinces in Southern Peru until the 1920s. In 1884 Chile and Bolivia signed a treaty formalizing the Chilean possession of the province of Antofagasta, turning Bolivia into a land-locked country.

Ironically, despite winning the war and being economically sound, Chile fell into a Civil War less than 10 years after the war's end. Even more ironically, the invention of the [[ Haber process]] thirty years later would render the nitrate deposits that served as the ''casus belli'' completely worthless--why mine nitrate when you can literally make it out of thin air (and water or natural gas, but whatever)? However, the greatest irony of all is that Chilean companies were not the ones that benefited from the war, but the British and German ones in payment of their help in the war.

!!Tropes Set during the war

* TheCaptain: Arturo Prat and Miguel Grau. Chilean and Peruvian national heroes respectively. Pratt led 21 men in an attempt to board one of the enemy's battleships, with most of them dying and impressing the Peruvians in the attempt. Grau would later send a letter to Prat's widow praising her husband's bravery and returning his personal effects. Grau would then go on to single handedly hold off the entire Chilean navy with just one ship, ''The Huáscar'', for almost six months.
** As commemoration of Grau's achivements, he's the last admiral of the Peruvian navy since from then on the maximum rank that one can achieve in the navy is rear admiral.
* ChildSoldiers: Most of the Army, of both sides, including the ones who died in ''La Batalla de la Concepción'' were teenagers at the time.
* CoolBoat: The Huáscar. So much you can still visit the ship today, but in Chile, which captured it during the war.
* KarmaHoudini: Chile after the war.
* LaResistance: The Peruvian resistance movement helped their army to keep the guerrilla war for about two more years.
* NeverLiveItDown: Bolivia, in regard to the loss of its seacost. To the point that the [[ Bolivian Navy]] ''still exists'' as an actual military force (operating on rivers and in inland Lake Titicaca). Bolivians 'commemorate' the loss of access to the sea as a national holiday, ''Dia del Mar,'' and Bolivia routinely seeks international mediation to resolve the problem.[[note]]Bolivia since 1992 has been utilizing a port near the city of Ilo, Peru, but this is subject to a 99-year non-renewable lease from the Peruvian government. Bolivia also has access to the Atlantic through Argentina via the Parana River and maintains port facilities in the Argentinian city of Rosario, but attempts to regain an actual coastline connected to the rest of the country remain frustrated by Chile.[[/note]]
* OfficerAndAGentleman: Peruvian Admiral Miguel Grau. It says something that the ones who gave him the name ''El Caballero de los Mares'' (The Gentleman/Knight of the Seas) were '''the Chileans themselves'''.
* OffscreenTeleportation: Peruvian Colonel Andrés Cáceres was nicknamed "The Warlock of Los Andes" for his ability to appear and dissapear at will in the mountain range (he knew them like the palm of his hand).
* [[OneSidedBattle One Sided War]]: Chile not only managed to hold its own against two nations, but occupied one country and forced the other to back down.
** In the other hand ''La Batalla de la Concepción'' (The Battle of La Concepción) and the same ''Batalla Naval de Iquique'' (Naval Battle of Iquique) were OneSidedBattle for the Peruvian/Bolivian Side. Those are remembered by the Chileans because they helped to rally the spirits for win the war.
* SuperSerum: The legend says, before going to fight any battle, the Chilean Soldiers got drunk with ''La Chupilca del Diablo'' (The Devil's Booze), a mix of strong Aguardiente and ''gunpowder''. It supposedly made the soldiers go absolutely berserker and able to ignore pain or fatigue.
* WeAreStrugglingTogether: The other reason for the peruvian defeat was the lack of unity amongst the generals.
* WorthyOpponent: Miguel Grau for the Chileans.

!!Depictions in fiction
* In ''Literature/TheLegacyOfTheGlorious'', the war is won by the Peruvian-Bolivian side: Spanish support for Perú allows them to buy two warships, which are enough to turn the Battle of Punta Angamos (where, in RealLife, Miguel Grau died) into a Peruvian victory, allowing for the liberation of the Bolivian coast and the eventual invasion of Chile.