La Frontera (geographical region)

La Frontera is the name given to a geographical region in Chile. La Frontera can denote either the area just around Bío Bío River or the whole area between the Bío Bío and Toltén River being in this later definition largely coterminous with the historial usage of Araucanía.

The name comes the times when it was the frontier of the Kingdom of Chile (a part of the Spanish Empire and later the Republic of Chile) with La Araucanía, the lands of the Mapuche nation following their great revolt in 1598.

Following the 1598 revolt and subsequent loss of the cities and forts south of the Bio Bio, the Spanish Empire established a system of forts and fortified towns between the Bio Bio and the Itata River and some within the Mapuche lands of Araucanía itself. This system continued through the 18th century and into the 19th century.

The first fortress rebuilt following the 1599 destruction of the forts in Catirai and its city Santa Cruz de Coya, the cities of Santa María la Blanca de Valdivia, San Andrés de Los Infantes and San Bartolomé de Chillán y Gamboa, was the reconstruction of the city of Chillán by the interim Governor Francisco de Quiñónez.

In 1601 Alonso de Ribera built Fort Talcahuano to defend remaining Spanish settlements near Concepción and Fort Lonquén on the Lonquén River to secure estancias that provided food to the army.

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