Picture warships firing on each other across the brown water of the Paraná, both flying the same flag. On September 29, 1893, in a channel between sandbars off El Espinillo Island, directly across the river from Rosario, the Argentine Navy fought itself. A rebellion had split the fleet down the middle, officer against officer, and now armored ships that had been built to defend the nation traded broadsides at a few thousand yards. It became the largest battle of armored naval units ever fought in Argentine history, and it took place not on the open sea but on a river, within sight of a major city's docks.
The roots of the fight lay in politics, not war. The Radical Civic Union, the UCR, had risen against a government it accused of fraud and corruption, the latest in a series of revolts that punctuated the era. The party itself was split: Leandro Alem favored seizing power outright, while his nephew Hipólito Yrigoyen, a future president, believed provincial uprisings could force the government to negotiate. When the national leadership ordered everyone to lay down their arms, Alem refused. Branding the call a betrayal, and backed by Swiss-German and Italian immigrant farmers from the surrounding colonies, he raised a rebellion in Rosario on September 25. The Argentine Revolution of 1893 had begun, and it would be decided on the water.
When word of the Rosario uprising reached Buenos Aires, the monitor ARA Los Andes set out up the Paraná, carrying weapons meant for forces loyal to the government. She never delivered them as ordered. On September 26, her own officers, led by a lieutenant, mutinied, arrested their captain, and turned the ship toward Rosario to arm the rebels instead. The captain's aide was shot dead in the struggle. That same morning, downriver, other warships had clashed near Martín García Island, the loyal cruiser 9 de Julio and ironclad Almirante Brown crippling a rebel torpedo boat. Never before had a civilian revolt cracked the Argentine Navy in two. Propaganda had done its work, eroding the trust between sailors and their officers until the fleet pointed its guns inward.
Having unloaded part of her cargo at Rosario, Los Andes slipped across to a fourteen-foot channel between two sandbars south of El Espinillo Island and held position without anchoring, using the shallow water to hamper the heavier government ship. The battle opened at 11:30, when Los Andes fired on the torpedo boat Espora; the nine-inch round fell twenty yards long. Espora answered with its smaller guns, buying time for the riverine battleship Independencia, trailing behind, to bring its main armament to bear. Captain Mansilla, commanding the loyal force, gave a deliberate order: aim for the upper deck and bridge, not the hull. He did not want to sink the rebel ship and drown its crew, fellow Argentines, fellow sailors. Torpedoes were ruled out for the same reason. Even at war with itself, the navy tried to spare its own.
The mercy did not save the rebels. Los Andes took so much punishment that her crew ran her aground to keep her from sinking, and the battered hull was pressed into service as a makeshift hospital ship. With her defeat, the rebellion lost its momentum. After talks between the mutineers and Alem, the UCR flags came down, Rosario surrendered, and Alem was placed under arrest; the army marched in on October 1. There is a long memory in this stretch of river. Eight decades earlier, on an island in these same waters, Manuel Belgrano had built a battery he named Independencia and first raised the Argentine flag. Now a ship bearing that same proud name had helped put down Argentines in revolt. The general Julio Argentino Roca, surveying the wreckage, called the duel of armored ships a milestone, comparing it to the legendary actions of the Peruvian ironclad Huáscar.
El Espinillo Island lies in the Paraná River off the Entre Ríos bank, directly opposite Rosario, Santa Fe, at roughly 32.95°S, 60.60°W. From the air the battle site reads as a maze of low, wooded islands, sandbars, and shifting channels in the broad braided river, the same shallows that shaped the 1893 engagement. The Rosario waterfront and the white spire of the National Flag Memorial stand on the western bank as clear visual references. The nearest airport is Rosario – Islas Malvinas International Airport (ICAO: SAAR, IATA: ROS), about 13 km west-northwest of the city; Buenos Aires lies roughly 300 km downriver to the southeast. Best viewed at lower altitude in clear conditions, when the river's intricate channels and islands are visible.