MundoAndino Home : Argentina Guide at MundoAndino

Boundary treaty of 1881 between Chile and Argentina

The Boundary Treaty of 1881 between Argentina and Chile was signed on the 23 July 1881 in Buenos Aires by Bernardo de Irigoyen, on the part of Argentina, and Francisco de Borja Echeverria, on the part of Chile with the aim to establish a precise and exact borderline between the two countries based on the Uti Possidetis principle. Despite dividing largely unexplored lands this treaty laid the groundwork for nearly all of Chile's and Argentina's current 5600 kms of shared borders.


Argentina declared its independence in 1816 and Chile did the same in 1818. Once the Spaniards had been expelled relations between the two nations soured primarily due to a border dispute: both claimed to have inherited overlapping parts of Patagonia.

The Chilean constitution of 1833 eastablished the Andes as its eastern boundary. This view of Chiles borders was challenged in 1853 by Miguel Luis Amunategui's book Titles of the Republic of Chile to Sovereignty and Dominion of the Extreme South of the American Continent, on which he put forward that Chile had valid arguments to claim all of Patagonia. [*] These claims traced Chilean claims back to the conquest of Chile in the 16th century by Pedro de Valdivia, arguing that Pedro de Valdivia obtained rights from the Spanish crown to establish a captaincy limited by the Strait of Magellan to the south. Pedro de Valdivia subsequently founded several cities through southern Chile with the goal of reaching the Strait of Magellan. However the remoteness of the region and the Mapuche in the War of Arauco limited further expansion to the south.

Occupation of the Straits of Magellan

The Republic of Chile founded Fuerte Bulnes in 1843, and later Punta Arenas in 1847, giving a strong impulse to steam navigation through the Strait of Magellan and probably averted the occupation of the strategicly crucial strait by the European powers or the United States. As stated by Michael Morris in "The Strait of Magellan":

''An 1837 French expedition of Dumont D'Urville surveyed navigational conditions in the Strait of Magellan and recommended that a French colony be established at the strait to support future traffic along the route.''

Treaty of 1856

Interests of Chile, Argentina and the great powers


Chilean trade and culture were orientated towards Europe and therefore the complete control of the strait was a core Chilean interest, in contrast the rest of Patagonia was seen by influential Chilean politicians as a worthless desert. This view was shared by Diego Barros Arana and was inspirated on Charles Darwin's description of the area as a useless moorland. [*]

The possession of the Straits of Magellan in all its length is of such great importance for Chile, that in that possession she sees linked not only her progress and development, but also her very existence as an independent nation. [*]

- Adolfo Ibanez


Mapuches and araucanized Indians had long time pillaged the Argentine southern frontier in search for cattle that was later taken to Chile through the Camino de los chilenos. The cattle was traded in Chile for weapons and alcoholic beverages. These tribes had strong connections with Chile and therefore gave Chile certain influence over the pampas. [*] Argentine authorities feared an eventual war with Chile over the region where the natives would side the Chileans and that the war would be therefore fought in the vicinities of Buenos Aires. [*]. Whether Argentina wanted to exclude Chile from the Atlantic and what significance "Atlantic" had then is still today a controversial issue.

In the 1870s, Argentina built the a more than 500 km long trench called Zanja de Alsina Argentina had undertaken the Conquest of the Desert from 1876 to 1878 to defeat the araucanized Indians occupying northern Patagonia and aspired to control the eastern third or, at a minimum, the eastern mouth of the strait.See Michael A. Morris, "The Strait of Magellan", Martinus Nijhoff Publishers, ISBN 0-7923-0181-1, page 63

The great powers

Great Britain and the USA did not directly intervene the distribution of land and maritime areas, except the mediation role of the US-Ambassadors in Santiago de Chile and Buenos Aires, Thomas A. Osborne and Thomas O. Osborne. The concern of the great powers was the free navigation through the strait. The USA-administration declared immediately before the negotiations leading to the treaty thatSee Erik Bruel, International Straits, Vol. II, Sweet and Maxwell, Ltd., London, England, 1947, p225. Cited in Michael A. Morris, "The Strait of Magellan", Martinus Nijhoff Publishers, ISBN 0-7923-0181-1, page 65:

"The Government of the United States will not tolerate exclusive claims by any nation whatsoever to the Straits of Magellan, and will hold responsible any Government that undertakes, no matter on what pretext, to lay or impost or check on United States commerce through the Straits. ".

Prior to the US-Statement, in 1873, via a diplomatic letter to major shipping nations Chile had already promised freedom of navigation through and neutralization in the strait.

The colonial powers, United Kingdom and France viewed Patagonia and Tierra del Fuego as Terra nullius. Jules Verne described in ''"The Survivors of the 'Jonathan'" his view of Patagonia:

The separated geographic location had as consequence that this part of the new world had not been incorporated to any civilized state up to the year 1881 even not by its nearest neighbour Chile and the Republic of Argentina. The Magalhaes archipelago belonged anybody

Regarding the position of the USA towards the region, on 28 December 1831, the US-Navy Captain Silas Duncan with the USS Lexington'' destroyed the Port Louis, Falkland Islands settlement in response to Argentine activities. The captain declared the islands to be free of government. Also the United Kingdom did not trust the Argentine rights on the region and (re)occupied 1833 the Falklands.

Negotiation and agreement

In 1874 Chilean minister Guillermo Blest Gana and the Argentine Minister of Foreign Relation Carlos Tejedor agreed to put the question on arbitration. However, the new Argentine president Nicolas Avellaneda, boosted by internal popularity, cancelled the agreement in 1875. Attempts to clear up the dispute about Patagonia were unsuccessful until 1881, when Chile was fighting the War of the Pacific against both Bolivia and Peru. At that time Chile had defeated Bolivia's and Peru's regular armies and had large contingents in occupying Peru and fighting Andres Avelino Caceres guerrillas. In order to avoid fighting Argentina as well, Chilean President Anibal Pinto authorized his envoy, Diego Barros Arana, to hand over as much territory as was needed to avoid Argentina siding with Bolivia and Peru.See Michael A. Morris, "The Strait of Magellan", Martinus Nijhoff Publishers, ISBN 0-7923-0181-1, page 62:

"From a Chilean perspective, possible Argentine entry into the War of the Pacific as a belligerant or even as an unfriendly power was a real threat so that Chile was concerned about assuring the neutrality of Argentina and others South American States."


The treaty defined the border in only three articles.

It defined the border down to latitude 52S as the line marked by the continental divide and the highest mountains of the Andes.

Article 1:

"The boundary between Chile and the Argentine Republic is from north to south, as far as the 52nd parallel of latitude, the Cordillera de los Andes. The boundary-line shall run in that extent over the highest summits of the said Cordilleras which divide the waters, and shall pass between the sources (of streams) flowing down to either side. "

Articles 2 and 3 recognise the area around the Strait of Magellan (South of the 52S) as Chilean as well as the islands south of Beagle Channel. Isla Grande de Tierra del Fuego was divided in two parts.

Article 2: In the area of the Strait of Magellan, south of the parallel 52S, the limit would go from Punta Dungenes north to Monte Dinero and then follow the small hills that separates the Atlantic watershed from the strait watershed until the latitude of Monte Aymond from where a straight line is drawn into the intersection of parallel 52S and the meridian 70W, and from there west along the 52 parallel until the last watershed divide point defined by article 1.

Article 3:

''"In Tierra del Fuego a line shall be drawn, which starting from the point called Cape Espiritu Santo, in parallel 5240', shall be prolonged to the south along the meridian 6834' west of Greenwich until it touches Beagle Channel. Tierra del Fuego, divided in this manner, shall be Chilean on the western side and Argentine on the eastern. As for the islands, to the Argentine Republic shall belong Staten Island, the small islands next to it, and the other islands there may be on the Atlantic to the east of Tierra del Fuego and of the eastern coast of Patagonia; and to Chile shall belong all the islands to the south of Beagle Channel up to Cape Horn, and those there may be to the west of Tierra del Fuego."

Furthermore the treaty defines the status of the Strait of Magellan:

Article 5

"The Straits of Magellan shall be neutralized for ever, and free navigation assured to the flags of all nations. In order to assure this freedom and neutrality, no fortifications or military defences shall be constructed on the coasts that might be contrary to this purpose."''

Article 6 states that older boundary treaties became obsolete and both countries agreed to submit any future disputes to the decision of a friendly third country.

The maritime border

The law of sea at the time of the 1881 treaty was quite far different from the articles of the 1982 Law of the Sea, which meant that Chile and Argentina adhered to the accepted practice of a three Nautical miles territorial sea. Therefore the treaty emphasized the delineation of land boundaries including islands but didn't stipulate the offshore limits that have since been expanded to 200 nautical miles.

Further disputes

According to the Argentine view of the treaty, called the Magellan/Atlantic transfer, the general agreement was that Argentina was an Atlantic country while Chile was a Pacific one. Chile has never accepted that and the Chilean view was confirmed by the Court of Arbitration in the Beagle dispute :

" .It is on this basis, as well as on the actual attribution of Patagonian territory to Argentina effected by Article II of the Treaty, that the Court reaches the conclusion that it was the antithesis Patagonia/Magellan, rather than Magellan/Atlantic, which constituted the fundamental element of the Treaty settlement.".

Some errors that would allow a Pacific coast for Argentina in Ultima Esperanza Sound and an Atlantic coast to Chile in San Sebastian Bay were later corrected. Different interpetations of the borderline north of latitude 52S led to the Arbitration of the British King Edward VII in 1902 .

Border disputes continued as Patagonia was still an unexplored area. The concept of the continental divide was easy to apply in northern regions but in Patagonia drainage basins crossed the Andes; this led to disputes over whether the highest peaks would be the frontier (favouring Argentina) or the drainage basins (favouring Chile). Argentina argued that previous documents referring to the boundary always mentioned the Snowy Cordillera as the frontier and not the continental divide. The Argentine explorer Francisco Perito Moreno suggested that many Patagonian lakes draining to the Pacific were in fact part of the Atlantic basin but had been moraine-dammed during the quaternary glaciations changing their outlets to the west. In 1902, war was again avoided when British King Edward VII agreed to mediate between the two nations. He established the current border in the Patagonia region in part by dividing many disputed lakes into two equal parts, most of these lakes still have one name on each side of the frontier.

The dispute that arose in the northern Puna de Atacama was resolved with the Puna de Atacama Lawsuit of 1899, though its real cause was out of the scope of the 1881 Boundary treaty and originated from transfers between Bolivia and Argentina of land occupied by Chile during the Pacific war.

File:Kanalarme.es.png|1904 Argentina changed its view of the Beagle channel

File:Ostmund.two.en.png|Two views of the east entrance of the Strait of Magellan

File:Resume.arg.cart.en.png|9 Argentine different interpretations of the treaty at the Cape Horn

File:Twotales.gif|Chilean (black) and Argentine (yellow) views of the Strait of Magellan

Additional protocols

To prevent relations from being aggravated, or to complement the Boundary treaty, a succession of protocols and declarations had to be signed:

1889 Zeballos-Matta Declaration (occupation of disputed areas confers no rights)

1893 Protocol (to resolve some of the pending issues)

1902 Pactos de Mayo May pacts


"The Survivors of the 'Jonathan'", also known as "Magellania" Les Voyages Extraordinaires. In French, Magellania, En Magellanie, or Les Naufrages du "Jonathan"., is a novel written by Jules Verne in 1897 and published posthumously in 1909, after it had been rewritten by Verne's son Michel under the title Les naufrages du "Jonathan".

The novel tells the story of a mysterious man named Kaw-djer who lives on the Nueva island, whose motto is "Neither God nor master". He refused any contact with western civilization relying on himself in order to survive and also provides assistance to the indigenous peoples of Magellania. However, the 1881 Boundary Treaty will destroy his paradise of individualist anarchism because it will end the state of terra nullius in the region.


Because each side was convinced of the legitimacy of its own claim the pretensions of the other party were considered as usurpatory, an ill-omened beginning that burdened the relations of both countries.

The treaty did resolve an immediate concern of each side, but subsequently it became evident that in the far south, about 42S to 52S, article 1 of the treaty posed problems of interpretation and application.

Some Argentine political publicists argue that articles 2 and 3 of the treaty were ambiguous, but they have to admit the truth that the later Argentine interpretations were refused by the international tribunal, that Argentine maps of the first decade also applied the Chilean interpretation and the two papal proposals as well as the treaty of 1984 maintained the Chilean interpretation of the treaty, at least in so far as the land border line.

There could be other reasons for the Argentine difficulties over the interpretation. Michael Morries observes about the Argentine policy:

Rearguard Argentine efforts has been made to gain recognition for some kind of shared management regime for the strait [of magellan], in order to mitigate what was perceived as the striking diplomatic defeat for Argentina in the 1881 treaty granting Chile control over the strait.

The Southern Patagonian Ice Field is the last still pending issue in order to apply the 1881 Boundary Treaty.

See also

Beagle Channel cartography since 1881

Beagle conflict

War of the Pacific


Michael A. Morris, "The Strait of Magellan", Martinus Nijhoff Publishers, ISBN 0-7923-0181-1, 237 pages.

External links

British Arbitration 1977: Beagle channel conflict: Report and decision of the Court of Arbitration, among other documents, it contents also the English and the Spanish version of the Boundary Treaty 1881.

British Arbitration 1902: The Cordillera of the Andes Boundary Case Argentina, Chile

Historia de las Relaciones Exteriores Argentinas Chapter 32 to 34, in Spanish Language

Karin Oellers-Frahm: Der Schiedsspruch in der Beagle-Kanal-Streitigkeit, Berichte und Urkunden: Max-Planck-Institut fur auslandisches offentliches Recht und Volkerrecht, in German language.

Didn't find what you were looking for.
Need more information for your travel research or homework?
Ask your questions at the forum about Argentina–Chile border or help others to find answers.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article Boundary treaty of 1881 between Chile and Argentina

Disclaimer - Privacy Policy - 2009