After Chile secured the sea with the victory at Angamos on October 8, 1879, the Chilean army prepared to assault Tarapacá province. Hence, an amphibious operation was launched at Pisagua on November 2, pushing the Allies inland and obtaining an unshipping point to unload troops and material. Right after Pisagua, two Allied squadrons were slightly outnumbered and crushed at Pampa Germania on November 6, and Col. Emilio Sotomayor held off a 7,400 men Allied attack on November 19 at Dolores dwell, near San Francisco. The string of victories made the Chilean commanders too confident, and with poor information recklessly attacked the outnumbering Peruvian army at Tarapacá on November 27, suffering a heavy defeat. Nevertheless, the Allies withdrew from Tarapacá department, leaving it in Chilean hands.