'''The Chincha Islands War''' (1864-1866) was a conflict between Spain and its former colonies Peru and Chile. Spain recognized Chile’s independence and they had a nice relationship, but they didn’t recognize Peru’s independence and wanted to charge them unpaid fees. When Peru didn’t want to pay them, Spain took over the Chincha Islands, a bunch of islands containing rich deposits of guano.

When Chile refused to supply the Spaniards with coal for their ships, they took the fuel by force, leaving them at war. Four months later, Peru allied with Chile and also declared war on Spain. Later, Ecuador and Bolivia entered the war at the side of their neighbors.

It was mostly a naval conflict, with one failed landing attempt by Spain, and it ended with the battered Spanish fleet retiring. However, the damage done to the Peruvian fleet and the Chilean commercial port of Valparaíso was catastrophic.

!!Tropes set during the war:

* AssInAmbassador
* CoolBoat: The Huáscar, which made its debut in this war.
* TheEmpire: Spain. [[TheRemnant A decadent one]], but still an empire.
* EnemyMine: Chile and Bolivia were at the brink of war when the Spaniards arrived, so they put aside their differences to fight them. [[WarOfThePacific However, they would soon begin clashing again]].
* GreatOffscreenWar: Argentina and Brazil did not join the war because they were busy with the War of the Triple Alliance.
* HumiliationConga: Since the Magallanes Channel was Chilean territory, the Spanish fleet had to make a trip around the world to get back to Spain.
* JerkAss: Spain. They sent an envoy to Peru with the title of Royal Commissary (a title used only on colonial domains, not independent nations). They also demanded a salute to the flag from Chile, ''the day before the anniversary of their independence''.
* MartyrWithoutACause: Spanish Admiral Pareja, who commited suicide after losing the naval battle of Papudo.
* PyrrhicVictory: Technically, Peru and Chile won, but the damage done to them crippled the naval domain of the first and the commercial capabilities of the latter.
* SolidGoldPoop: The guano that made the Chincha Islands so valuable? Accumulated bird poop. The stuff is rich in nitrate, which is needed for explosives and fertilizer. Until the discovery of the [[DichterAndDenker Haber Process]] the early 20th century, nitrate was not readily available, so in order to grow food and have operative guns, you needed large sources of nitrate...and guess what the best kind was? The importance of guano eventually led to Chile and Peru [[WarOfThePacific getting in a war with each other]].
* VestigialEmpire: Spain had been decaying as an empire since the loss of most of its colonies; they barely had the military force or the global presence of previous times. The humilliation suffered by them would conclude later with the loss of all its remaining colonies in the Spanish-American War.
* WoodenShipsAndIronMen
!!Depictions in fiction