by
Cayetano Descalzi. France and Britain imposed a five-year-long naval blockade on the Argentine Confederation ruled by
Juan Manuel de Rosas. It was imposed in 1845 to support the
Colorado Party in the
Uruguayan Civil War, and closed Buenos Aires to naval commerce. Anglo-French
merchantmen trespassed into the
internal waters of Argentina in order to sell their products, as Rosas maintained a firm
protectionist policy. A key engagement in the blockade was the
Battle of Vuelta de Obligado, where a combined British and French fleet forced their way into the
Paraná River despite fierce resistance from the Argentine forces: although the British and French forces routed the Argentine forces, inflicting significant casualties, the damage to European fleet was so extensive that they had to stay for 40 days in Obligado to make repairs. The expedition also proved a commercial failure, as
Paraguay proved to be less wealthy than expected and merchant ships were forced to return with many of their goods unsold. On their return the convoy again faced fierce resistance, with several merchant ships sunk by the cannon fire of the Argentine forces. Whilst the British commander
William Ouseley requested additional forces to support a new and continued campaign, a number of factors compelled the British to break with their French allies; the outcome of the expedition, and the total cost of the short victory and limited commercial opportunities quickly changed British attitudes. Besides, Argentina owed a substantial debt to
Barings Bank and the country's suspension of payments due to the blockade had caused financial concerns for the British.
The Times had also printed an allegation that Ouseley had a personal financial interest in the blockade, causing a political scandal. Tomás Samuel Hood was sent to Buenos Aires with the instruction to negotiate a settlement with Rosas at all costs. ==Negotiations==