When Portuguese raiders founded Colonia do Sacramento on the eastern shore of the Río de la Plata estuary in 1680, the colonial authorities in Spain were justifiably alarmed. Their possessions in the New World were not only threatened by European adversaries, but now the Portuguese in Brazil had established a bridgehead in the Río de la Plata that allowed them to make inroads into the vast lowlands of this river system and, from there, to ultimately threaten Alto Peru, the silver source of the Spanish crown in South America.
After an initial success in dislodging the intruders, the colonial authorities in Madrid decided to build a stronghold on the eastern shore of the Río de la Plata (Banda Oriental) to ascertain their presence in these remote territories and deter future thrusts from rival nations. With this strategy in mind, the garrison-settlement of San Felipe de Montevideo was founded in 1723....
