After the
naval battle of Iquique of 21 May, the Peruvian fleet lost the armored frigate
Independencia to a wooden schooner,
Covadonga. This obliged Rear Admiral Miguel Grau to renounce to attack and to adopt a harassing strategy, avoiding by all means a direct encounter with the bulk of the Chilean navy. Aboard the monitor
Huáscar, Grau made several incursions into Chilean waters, successfully challenging the enemy's domination along the coast. Under his command,
Huáscar sank or captured 14 transports, one of them carrying an entire cavalry regiment. This last setback was considered a humiliation by the Chilean public opinion, and sparked several protests against the government. Besides, the Commander of the Chilean fleet
Juan Williams Rebolledo resigned on 5 August. His poor command left his ships incapable of sailing without important repairs. The Chileans lost almost a month restoring the vessels to combat condition again. Therefore, the newly appointed Commander of the Navy, Commodore
Galvarino Riveros Cárdenas, couldn't sail until September. By 30 September, Riveros was notified that the corvette
Unión was sailing to
Panamá to escort five small ships with torpedoes bought from the
United States. The Chilean fleet sailed again on 1 October, now carrying War Minister
Rafael Sotomayor. The preceding week, the government had ordered the fleet to hunt down the
Huáscar at all cost. In a council held aboard Riveros' flagship, the armored frigate
Blanco Encalada, it was decided to set course to
Arica, hoping to find
Huáscar there. But, on 7 October, Riveros was informed that Grau had been sighted sailing north at
Coquimbo, halfway between Arica and
Valparaíso. Therefore, a new strategy was set up to capture the Peruvian monitor. Divided in two divisions, Riveros with the slower ships would move close to shore, while Latorre would sail about 35 km from shore with the faster ships. So, the fleet was divided as it follows: • 1st Division—Commodore Galvarino Riveros Cárdenas. • Armored frigate
Blanco Encalada: Commodore Galvarino Riveros Cárdenas • Wooden schooner
Virgen de Covadonga: Lt. Captain Manuel Orella • Transport
Matias Cousiño : Lt. Captain Augusto Castleton. • 2nd Division—Commander Juan Jose Latorre • Armored frigate : Commander Juan Jose Latorre • Corvette ''
O'Higgins'' : Lt. Captain
Jorge Montt Alvarez • Gunned Transport
Loa : Lt. Captain Javier Molinas Gacitua.
Chilean strategy On 1 October, Riveros gathered his officers and communicated the order of hunting down the Peruvian vessel at
Arica. The same day, Grau in his flagship
Huáscar ordered to sail along the coast as far south as
Coquimbo, accompanied by the corvette
Unión. Since the Chilean fleet sailed close to the shore and the Peruvians were farther out in the open sea, both formations didn't spot each other. At Mejillones, on 7 October, a plan was approved to deceive the Peruvian ships. Riveros' division would wait for Grau at
Antofagasta while Latorre would set up an east–west barrier-like formation about from shore. If Riveros could spot
Huáscar, he would follow and keep her from retreating to south until Latorre could engage. During the night the Peruvian warships were sailing off the Chilean coast to Arica, when they saw the lights of Antofagasta. Admiral Grau decided to engage any Chilean vessel at the port, intending to inflict some damage. At 01:10 h. on 8 October,
Huáscar searched the bay without encountering any targets. She came up with
Unión at 03:00 hrs, and both resumed their northward heading. At the same hour, lookouts on
Blanco Encalada saw two smoke columns on the horizon. Simultaneously, Grau was informed that there were three smoke columns to north. Both enemies spotted each other and the Peruvian ships turned back south. Riveros ordered a speed reduction of his to make Grau think it was possible to turn back north and sail for Perú. At 05:40 h., both Peruvian ships began to slowly turn once again north. Then, Riveros increased the speed of
Blanco Encalada to get closer to the Peruvians and to discourage Grau from turning back south. At 07:15 hrs, steaming northward, the two Peruvian vessels spotted smoke columns ahead; it was the incoming Latorre's division. Since the Peruvian
Unión could manage 13 knots, she was able to sail northeastward and escape, but the
Huáscar had to maintain course and fight. ==The Struggle==