With tensions high between Peru and Spain over the disputed Chincha Islands, Peruvian President Pedro Deiz Canseco's careful approach brought his fall and replacement by General Mariana Ignacio Prado, who was declared "Dictator." A far more active anti-Spanish policy followed, with naval clashes, an alliance with Chile and an eventual declaration of war in January 1866. (By John Osborne)
Source Citation
"Peru," The American Cyclopedia and Register of Important Events of the Year 1865 ... (New York: D. Appleton and Co., 1869), 697-699.