The Spanish of Río de la Plata

Buenos Aires was founded in 1536 by Pedro de Mendoza. However, the indigenous communities of the pampas later forced the evacuation of the city, and its citizens relocated to Asunción. In 1580, Buenos Aires was refounded by colonists from Spain and other colonies.

In the early 17th century, Argentinian cowboys moved to the Eastern Bank (Banda Oriental), where they established a thriving market in leather and meat. Some traders opened businesses in Uruguay. In 1680, the Portuguese established their first capital on the Uruguayan coast.

Buenos Aires was established as the provincial capital of Río de la Plata, the importance of which grew with the route across the Atlantic. It was from this city that the colonists left in 1726 to found Montevideo, in response to Portuguese advances. In 1776, the Viceroyalty of Río de la Plata was created.

Following the independence movements in the early 19th century, Uruguay was annexed to Brazil for a time. Midway through the century, Argentina also became home to millions of European immigrants, the majority of them Italian.

More than two thirds of the Uruguayan population live in Montevideo. In many ways, Uruguayan Spanish is a partial extension of the language spoken in Buenos Aires. However, the Portuguese influence is also discernible in some of the dialects of the northern region.

Argentina is the largest Spanish-speaking country in the world and, although many dialects can be found across its territory, these are all overshadowed by the Buenos Aires vernacular, which has been heavily influenced by Italian immigration. This fusion also produced a contact language known as Cocoliche.

Uruguayan Spanish shares almost all its vocabulary with the variant spoken in Buenos Aires, including much of its Lunfardo vernacular, the jargon used by young people, professionals, and in sports. On the other side, the Brazilian border has brought about a particular dialect known as "Fronterizo".