Chilean expansionism

Chilean expansionism refers to the foreign policy of Chile to expand its territorial control over key strategic locations and economic resources as a means to ensure its national security and assert its geopolitical power in South America. Chile's significant territorial acquisitions, which occurred mostly throughout the 19th century, paved the way for its emergence as one of the three most powerful and wealthiest states in South America during the 20th century.

After achieving its independence from Spain in 1818, Chile held control of territory spanning roughly the same boundaries of the colonial general captaincy that was under the control of the Spanish Empire's Viceroyalty of Peru. Under the uti possidetis iuris principle that delimited the international boundaries of the independent South American states, Chile bordered at its north with Bolivia in the Atacama Desert and at its east with Argentina. To the south Chile claimed all lands west of the Andes but controlled only the area down to Bío Bío River plust the area between Valdivia and Chiloé, with the rest either belonging to independent Mapuche of Araucanía or being sparsely populated by other tribes. The uti possidetis system proved ephemeral, nonetheless; the lack of formal border treaties caused disputes throughout the continent.

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