Brazil–Suriname border

Waiting for the neighbours

Colonial outposts in the Guianas clung to the coast and rivers, and the interior was hard to cross. The Dutch, on friendly terms with Brazil, asked to wait until France and Britain had settled their own borders with Brazil. After Brazil’s treaties with France in 1900 and Britain in 1904, the Netherlands signed a boundary treaty with Brazil in Rio de Janeiro on 5 May 1906, defining the line as the watershed between the Amazon basin to the south and the basins of rivers flowing north into the Atlantic.^[1]

Brazilian and Dutch commissions were agreed in 1931 and began work in 1934, led by the Dutch vice-admiral Conrad Carel Käyser and the Brazilian Brás de Aguiar. Their report, signed in Belém on 30 April 1938, gave the length as 593 km and recorded 59 boundary posts. The line has not changed since Suriname’s independence.^[1]

“…door de lijn der waterscheiding tusschen het stroomgebied der Amazone, in het Zuiden, en de bekkens der waterstroomen, die zich noordwaarts in den Atlantischen Oceaan uitstorten.”^[1]

The ends of the line

In the west, the point where Suriname, British Guiana and Brazil meet was fixed in 1936 at the source of the Kutari river, as the Dutch had proposed in 1933; Admiral Käyser signed the map with the Brazilian and British commissioners.^[2]

In the east, the Brazilian border itself is not disputed, but the land just north of it, between the Itany and Marouini rivers, is claimed by Suriname and administered by France.^[3]