An improvised fleet with a communication problem

The Junta bought five merchant vessels and armed three of them - Invencible, 25 de Mayo, and América - with obsolete weapons gathered for the emergency. Local recruiting could not produce enough experienced seamen, so the new service relied on foreign officers, including Maltese and French commanders. Much of the rank and file spoke Spanish while several officers did not, creating an immediate command-and-control weakness aboard improvised warships. The force was ordered upriver with troops and artillery to reinforce Manuel Belgrano after his reverses in Paraguay. Montevideo learned of the plan and sent Jacinto de Romarate with seven better-armed ships to intercept it, turning a transport mission into a battle the revolutionary flotilla was poorly prepared to fight.