The Arauco War was a long-running conflict between colonial Spaniards and the Mapuche people, mostly fought in the Araucanía region of Chile. The conflict began at first as a reaction by the Mapuche to the Spanish conquerors attempting to establish cities and force the natives into servitude. It subsequently evolved over time into phases comprising drawn-out sieges, slave-hunting expeditions, pillaging raids, punitive expeditions, and renewed Spanish attempts to secure lost territories. Abduction of women and war rape was common on both sides.
The Spaniards penetrated into Mapuche territory during the conquest of Chile in the 16th century. They were stopped at the Battle of Curalaba in 1598 and the destruction of the Seven Cities. Afterward the two forces established a clear frontier between the Spanish domains and the land of the independent Mapuche. From the 17th to the late 18th century the Mapuche lonkos and Spanish royal governors held a series of parliaments. The war devolved to sporadic pillaging carried out by both sides.
In the words of Philip II, this conflict cost the largest number of Spanish lives in the New World. It became known as the Flandes indiano ("Indian Flanders"), in reference to the Eighty Years' War in Europe.
Causes of its origin and length
Initially, the key area of conflict that the Spanish attempted to secure south of Bío Bío River were the valleys around Cordillera de Nahuelbuta. The Spanish designs for this region was to exploit the placer deposits of gold using Mapuche (slave) labor from the densely populated nearby valleys. To serve the Spanish in gold mining was a deadly activity that killed many Mapuches. Lacking a tradition of forced labor like the Andean mita, the Mapuches largely refused to serve the Spanish, setting the stage for the conflict. It has been conjectured that gold mining was already occurring in Mapuche lands south of the Inca Empire prior to the Spanish arrival and that this would have allowed the Spanish to rapidly identify places with gold.
On the other hand, the Spanish, in particular those from Castile and Extremadura, came from an extremely violent society. According to Diego de Rosales, 17th-century Mapuche chief Lientur would have explained that he preferred to "die warring, than in a bad peace". Analysing the situation in the 1650s, the Real Audiencia of Santiago opined that slavery of Mapuches was one of the reasons for constant state of war between the Spanish and the Mapuches.
Jesuits sought to diminish hostilities and end the war altogether by converting Mapuches to the Christian faith. They temporarily succeeded in enforcing the Defensive War (1612–1626) policy, but their conversion attempts foundered on Mapuche leaders' staunch defense of polygamy, which was unacceptable in the Catholic faith. This insistence on polygamy has been explained as Mapuche chiefs valuing it as a way to establish more alliances through marriage than monogamous marriage allows. Polygamy may also have been valued as important population strategy in war times when the Mapuche male population was unstable.
An antecedent of the Arauco War was the Battle of Reynogüelén, which occurred in 1536 between a detachment of Diego de Almagro's expedition and a large group of Mapuches, near the confluence of the Ñuble and Itata rivers. The beginning of the war comes with the campaigns of conquest of Pedro de Valdivia.
Campaigns of Pedro de Valdivia (1540–1553)
During the early phase of the Conquest of Chile, the Spanish conquistador Pedro de Valdivia conducted a nine-year campaign to secure central Chile. Arriving in central Chile, Pedro de Valdivia was confronted by the toqui Michimalonco, who a couple of years before had expelled the Incas from the northern parts of the Mapuche lands. The Spanish and Mapuche faced each other in the Battle of Mapocho, in which Valdivia was victorious. Michimalonco decided to make a tactical retreat to gather more contingents and to expel the Spanish invaders with a surprise attack, but the Spanish learnt of this and decided to head for where the Mapuche were gathering: at the Battle of Chillox, Michimalonco was defeated again.
The resounding victory left Pedro de Valdivia confident enough to decide to found the city of Santiago in the Mapocho valley and begin organizing the nascent colony. After a few months of settlement, Pedro de Valdivia gathered his forces and went directly to attack the fortress of Michimalonco in Paidahuén, leading to the battle of Paidahuén where the Mapuches were completely defeated and Michimalonco taken prisoner. To obtain his freedom, Michimalonco offered the Spanish the ownership of the Marga Marga gold pans, which had belonged to Michimalonco since the expulsion of the Incas. With this, Michimalonco and his imprisoned men were released and Michimalonco set some of his vassals to the exploitation of the gold on behalf of the Spanish.
After gold-panning for the Spanish for a while, Trangolonco, Michimalonco's brother, revolted. He defeated the Spaniards in Marga Marga, destroying the Spanish settlement, then defeated the Spanish in Concón, burning a ship under construction in the bay: only one Spaniard and a slave escaped. Trangolonco called on all the indigenous chiefs of the Cachapoal, Maipo and Mapocho valleys to send forces to join Michimalonco so that, just as he did with the Incas, he might expel the Spanish from the Wallmapu. In this way, he managed to gather around 16,000 warriors.
On September 11, 1541, Michimalonco attacked: the resulting Destruction of Santiago, left barely a handful of Spaniards surviving. Then Michimalonco applied his “empty war” strategy, which consisted of not giving the Spaniards any type of food or supplies so to force them to go back to Peru. The Spanish barely managed to resist and there were a series of skirmishes between Spanish and Mapuche forces.
After a large number of confrontations between the forces of Valdivia and those of Michimalonco, the capture by de Valdivia of three forts held by Michimalonco in the Andean mountain range of the Aconcagua River, enabled the Spanish finally to gain control over the valleys of Cachapoal, Maipo and Aconcagua by the end of 1543; resulting in the withdrawal of Michimalonco's forces towards the north.
In 1544, Michimalonco headed to the Limarí River valley to cut off Spanish land communications between Chile and Peru. With the forces of his Diaguita allies in this region added to his own, Michimalonco regained his strength, winning some victories against the Spanish advances, and forcing Pedro de Valdivia into commanding his army himself; engaging the Mapuche-Diaguita forces at the battle of Limarí, where Michimalonco was again defeated.
Pedro de Valdivia then sent Juan Bohón to found the City of La Serena at the mouth of the Elqui River.
In 1544, Valdivia sent out a naval expedition, comprising the barques San Pedro and Santiaguillo, under the command of Juan Bautista Pastene, to reconnoitre the southwestern coast of South America as far as the Strait of Magellan. The expedition set sail from Valparaíso, entered the bay of San Pedro, and made landings at what is now known as Concepción and at Valdivia, which was later named in honour of the commander. Encountering severe storms further south, he then returned to Valparaiso.
Valdivia himself set out in 1546, with sixty horsemen plus guides and porters. Crossing the Itata River, he was attacked by Mapuche warriors in the Battle of Quilacura near the Bío-Bío River. Realizing that it would be impossible to proceed in such hostile territory with so limited a force, Valdivia elected to return to Santiago after finding a site for a new city at what is now Penco and that would become the first site of Concepción.