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Colonia del Sacramento was founded by the Portuguese in 1680 under the leadership of Manuel Lobo, Governor of Rio de Janeiro. The settlement was established opposite Buenos Aires and was of strategic importance in the dispute between Portugal and Spain over influence and trade in the Rio de la Plata area.
The city changed hands repeatedly, so Portuguese and Spanish features of urban planning and architecture coexist in its historic centre. This layered character was one reason the quarter was included on the UNESCO World Heritage List.
On a walk, its history is easiest to trace through the Portón de Campo, Calle de los Suspiros, Plaza Mayor, ruins, and museum exhibits. If the exact stages of changes in control matter, take a tour or follow an official museum route rather than relying only on legends about individual houses.