Malaspina expedition (1789-1794)
Spain's great Enlightenment scientific circumnavigation: five years, the corvettes Descubierta and Atrevida, hydrographic surveys and natural-history collections from the Americas to the Philippines and the Pacific. Its results went largely unpublished for a century after its commander fell to court politics and prison — the reason the expedition is under-told, stated on the record.
Why this wins its question: Cook and La Pérouse dominate the genre's memory; Malaspina's voyage — comparable in scale and science — is missing from it for a documented political reason. This object cites the modern scholarly edition of the commander's journal and the academic biography, and explains the obscurity instead of just lamenting it.
Claims
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The expedition commanded by Alejandro Malaspina sailed from Cádiz in 1789 with the purpose-built corvettes Descubierta and Atrevida and returned in 1794, having surveyed the Pacific coasts of the Americas and crossed to the Marianas, the Philippines, and the southwest Pacific.
Its program combined hydrography, astronomy and natural history with confidential political reporting on the state of the colonies, in the manner of the Cook and La Pérouse voyages it was designed to match.
After returning, Malaspina pressed reformist proposals at court, was arrested in 1795 amid palace intrigue and imprisoned, and the expedition's results remained largely unpublished until the late 19th century — the direct cause of its historical obscurity.