The River Plate (known locally as Rio de la Plata) is perhaps better remembered today as the site of the first naval battle of WWII (known as Battle of the River Plate), but it is also where “this side of the river” led to an Oriental Republic.
The story starts in late 18th century, when Portugal and Spain agreed to divide South America in a number of treaties, which included an area to the east of the Uruguay River and north of the River Plate that was given to Spain and was called the Banda Oriental del Uruguay, simply meaning “Eastern Strip of the Uruguay River”.
With the independence of the US, and with Spain falling under French control during the Napoleonic wars, this created an atmosphere of defiance and independence which erupted in 1810 with the May Revolution and the eventual creation of United Provinces of the Río de la Plata incorporating most of Spanish South America and based in Buenos Aires. Despite initially attempting to capture Montevideo and surrounding lands from Spain, the Uniterians became allies, this betrayal prompting the people of Banda Oriental to separate themselves and establish the League of Free People, based in Montevideo.
This new found freedom did not last long, and the United Kingdom of Portugal, Brazil and the Algarves soon invaded and occupied this area in what was to become the Cisplatine War, renaming it the Cisplatina Province. Cisplatina simply meant “This side of the River Plate”.
The spanish speaking residents resented the Brazilian occupation and a revolutionary group led by Juan Antonion Lavalleja called themselves the Treinta y Tres Orientales (Thirty Three Orientals) as an objection to the name of the province, as they insisted they were not onBrazil’s side of the River, but rather on the Eastern (Oriental) side of the River Uruguay.
By 1825 the revolutionaries decided to declare independence and war broke out, with the Argentine navy coming to the revolutionaries’ assistance. Neither side was able to gain the upper hand, and by 1828 a stalemate was recognised. The British, who relied on heavy trade in the region, forced both sides to sign the Treaty of Montevideo, finally giving the Uruguayans their independence.
As a reminder of their revolution, the new country was officially declared as República Oriental del Uruguay, though most people recognise it simply as Uruguay.