The 1982 war brought the sovereignty dispute between Argentina and the United Kingdom over the Malvina Islands to the forefront of global attention . However, the core of Argentina's claim is based on a historical and legal legacy that dates back to the early years of its independence.

In this context, a handwritten letter by General José de San Martín acquires paramount importance , as it constitutes irrefutable documentary evidence of the knowledge and administration of the archipelago by the authorities of the United Provinces of the Río de la Plata.

The document, dated in Mendoza on August 14, 1816 , just forty days after the Declaration of Independence , was addressed to Colonel Antonio Beruti . In it, San Martín , immersed in the titanic preparation of the Army of the Andes, requests that "all those of high class who are imprisoned... sentenced to the prisons of Patagones, Malvinas or others" be sent to the capital.

This specific request, with the clear intention of incorporating these men into the liberation campaign to "make them useful to the State" , demonstrates that the Malvinas were considered a territory clearly under patriotic jurisdiction , used as a place of detention and, therefore, integrated into the incipient administrative structure.

This manuscript is a fundamental piece that is integrated into the solid framework of the Argentine claim, based on the principle of uti possidetis juris of 1810, by which the new nations inherited the territorial limits of the old Spanish viceroyalties.

The explicit mention of San Martín is not accidental ; it reinforces the continuity of the exercise of sovereignty over the islands and refutes any theory that seeks to deny their belonging to the geographical and political space inherited from Spain.

The letter, acquired at a London auction in 1988 by the Argentine diplomatic corps and donated to the Ministry of Foreign Affairs, where the original is kept, transcends its anecdotal value. It stands as material testimony that, from the very beginning of the nation, the Malvina Islands were an inseparable part of the national project, a knowledge that the Liberator himself carried with him while planning the campaign that would change the destiny of South America .