Ecuador–Peru border

A colonial muddle

In Spanish times the land east of the Andes between the Marañón and Caquetá rivers passed back and forth between the viceroys of Lima and Bogotá, so at independence nobody could say whose it was. Peru was ready to give up the land north of the Marañón after losing a war to Colombia in 1829, but Ecuador then split from Colombia and the balance tilted to Peru.^[1]

When Ecuador offered land in the Amazon, the Oriente, to its European creditors in 1857, Peru went to war in 1859–60 and occupied Guayaquil.^[1] Ecuador struggled to settle the Oriente, which was easier to reach from Peru, and from 1853 Peru pushed up the rivers from Iquitos.^[1] Attempts at a settlement failed: a treaty in 1890 that Peru’s congress refused to ratify, and an arbitration by the King of Spain, abandoned after its likely award leaked in 1910 and war nearly broke out.^[1]

War in 1941 and the Rio Protocol

In 1936 the two agreed to keep the status quo in the disputed zones while they talked in Washington, and that line became a de facto border. The talks broke down in 1938.^[1] On 23 July 1941 Peru, alleging Ecuadorian incursions, invaded with forces outnumbering Ecuador’s at least four to one. It occupied the province of El Oro and kept advancing in the Amazon after a ceasefire on 31 July.^[1]

With the Americas rallying against the Axis after Pearl Harbor, foreign ministers met in Rio de Janeiro in January 1942, and Brazil’s Oswaldo Aranha pressed Ecuador to settle. The Protocol of Peace, Friendship and Boundaries was signed there on 29 January 1942. Ecuador gave up its hope of reaching the Marañón but kept the eastern flanks of the Andes and was granted free navigation on the Amazon. The United States, Argentina, Brazil and Chile guaranteed it until the border was fully marked.^[1]

“From the Quebrada de San Francisco, the watershed between the Zamora and Santiago Rivers, to the confluence of the Santiago River with the Yaupi”^[1]

The watershed that wasn’t there

The protocol ran the line along the watershed between the Zamora and Santiago rivers. US Air Force aerial photographs later showed that one of the geographic features the protocol listed did not exist, and that stretch was never marked.^[1][2] Ecuador, where the protocol was deeply unpopular, used this to seek a revision that would give it access to the Marañón. In 1960 President-elect José María Velasco Ibarra declared the protocol null because it had been imposed by force, though Ecuador never formally denounced it.^[1]

In 1980 the Geographer published Krieg’s view that the dispute was quiescent but could flare again.^[1] It did: Ecuador and Peru fought in 1981 and again in 1995 over the unmarked area.^[2]

The 1998 peace

On 26 October 1998 the two countries signed a peace treaty in Brasília, with the presidents of Peru, Ecuador and Brazil looking on. It fixed the disputed 78 km section along the heights of the Cordillera del Cóndor, as Peru had claimed.^[2]

Ecuador received a compromise. Tiwintza, a hill its troops had held against repeated assaults in 1995 and where Ecuadorian soldiers are believed to be buried, stays under Peruvian sovereignty, but one square kilometre of it was given to Ecuador’s government as private property. The treaty also called for two neighbouring national parks in the disputed area and a commission to settle future border issues peacefully.^[2]