Peru (Per-oo'), a republic of South America, extending from near 2° to 17° 20' S. lat. Previous to the annexations by Chili, the Peruvian territory stretched southward to 22° 10', with a length along the Pacific coast of 1400 miles, and a width of 300 miles. It borders on the Pacific, Ecuador, Brazil, Bolivia, and Chili. The area is roughly estimated at 500,000 sq. m. The population was in 1900 estimated to be about 4,600,000, the aboriginal Inca Indians forming 57 per cent., the Mestizos or half-castes 23 per cent., and the rest being of pure Spanish descent, negroes, Chinese, etc. The Coast extends from the base of the Andes to the Pacific Ocean, and consists of a sandy desert crossed by some forty rivers along whose banks there are fertile valleys; the Sierra, or region of the Andes, about 250 miles wide, contains stupendous chains of mountains, elevated plains and tablelands, warm and fertile valleys and ravines; and the Montana, skirting the eastern slopes of the Andes, consists of tropical forests traversed by great tributaries of the Amazon. The absence of rain on the coast strip of land between the mountains and the sea is caused by the action of the lofty uplands of the Andes on the trade-wind; the last particle of moisture is wrung out of the wind by the very low temperature, and deposited as snow, and the wind rushes down to the Pacific coast, cool and dry. From November to April there is usually constant dryness on the coast, from June to September the sky is obscured for weeks by mist, sometimes accompanied by drizzling rain. The maximum temperature is about 78° in summer and 60o in winter. Since 1570 there have been seventy destructive earthquakes recorded on the west coast, including those of 1868 and 1877.

The Peruvian Andes attain 22,000 feet. The mountain-system consists of three chains or Cordilleras. Two of these chains, running parallel and near each other, are of identical origin. The western one is the maritime cordillera and comprises the volcanoes. The eastern cordillera is a magnificent and almost continuous range, in great part of Silurian formation, with clay-slates and eruptive granitic rocks. The western cordillera is cut through by several streams which flow into the Pacific, and the eastern cordillera by six tributaries of the Amazon, but the central chain is an unbroken water-parting, consisting mainly of crystalline and volcanic rocks. The valleys and plateaus between these ranges form the Sierra of Peru, and include every variety of climate and scenery. They may be divided into four sections, commencing from the north; in the third is Cuzco, the capital of the Incas, while the fourth section is the basin of Lake Titicaca, about 150 miles in length and breadth. The lake itself is 80 miles long, and 12,545 feet above the level of the sea. The Sierra of Peru is the original home of the potato. The animals which specially belong to the Peruvian Sierra are the domestic llamas and alpacas, and the wild vicunas, the viscacha, the chinchilla, deer, dogs, and foxes; notable among birds are the condor and the flamingoes, geese and wading birds of Lake Titicaca.

The Montana is the region of tropical forests within the basin of the river Amazon; the forests drained by the Maranon, Huallaga, and Ucayali forming the northern portion. The whole length of the Montana, from the Maranon to the Bolivian frontier, is 800 miles. The subtropical portion, comprising the eastern slopes of the Andes, is the region of the cinchona-trees, and of the coca, and here coffee and cacao of the finest quality are cultivated. From the forest-covered plains come india-rubber, sarsaparilla, and a great variety of useful and ornamental timber. The fauna of the forests includes monkeys, bats, bears, pumas, jaguars, tapirs, wild cats, deer, and many rodents; with curassows, ibises, cranes, spoonbills, parrots, toucans, and many snakes. The chief crops of the fertile valleys on the coast of Peru are sugar, cotton, and grapes. Good wine and spirits are made; and before the disastrous Chilian war (1879) mulberries, silkworms, and cochineal were successfully cultivated. The ex-ortation of guano from the Chincha Islands began in 1846 and ended in 1872, the supply being exhausted; and the nitrates of Tarapaca were seized and annexed by Chili. The staple exports of the Sierra of Peru are silver and wool, the great centre of mining industry being at Cerro Pasco. Copper is also exported; and there are rich gold washings. The total value of metals exported in 1903 was 952,812. From the Montana the exports are cinchona bark, coca, coffee, cacao, tobacco, india-rubber, and sarsaparilla, besides maize and wheat.

In the five years 1899-1903 the exports varied from $33,600,000 to $47,300,000, and the imports from $21,230,000 to $34,300,000 (10 'soles' or dollars = 1), about one-half of the total trade being with Great Britain. The exports to Britain are chiefly copper and silver ore, wool, cotton, rubber, sugar, and guano; the imports from Britain being cotton and woollen manufactures, ironwork and machinery, and jute goods. In the five years to 1903 the revenue varied from $13,500,000 to $16,472,000, and the expenditure from $12,630,000 to $14,800,000. The system of railways consists of a dozen short lines in the coast-valleys, and of two long lines across the Andes. The first of these, from Callao and Lima to Oroya, was commenced in 1870, and tunnels the Andes at an altitude of 15,645 feet. The other great line across the Andes connects the port of Mollendo with Puno on the shores of Lake Titicaca, passing by Are-quipa. The summit is crossed at a height of 14,660 feet, and the line is 346 miles long. Great public works were mainly responsible for raising the debt from 4,400,000 (1868) to 49,000,000 (1872). The financial difficulties culminated with the disastrous war with Chili, when the nitrate of Tarapaca, the chief resource of Peru, passed into the hands of the enemy. The payment of interest ceased in 1876, having been regularly paid since 1849; in 1890, when the outstanding interest of the debt amounted to 23,000,000, the bondholders had the railways, mines of guano deposits, and state lands ceded to them for 66 years; and Chili made itself responsible for some part of the payment.

The bulk of the Peruvian population is composed of the aboriginal Inca Indians, whose language, called Quichua, is still spoken in the Sierra. The Incas had attained to a high state of civilisation before the arrival of the Spaniards: they cultivated many of the arts, and had some knowledge of astronomy. Three centuries of oppression under Spanish rule have deteriorated the character of the Inca Indian, but he is still industrious and honest. The wild Indians of the Montana were never subjugated by the Spaniards. Spanish administration caused a rapid diminution of the population. The Indians of the Sierra were decimated, while those of the coast-valleys disappeared altogether. Negro slaves were then introduced, and kept in bondage until 1855, when slavery was abolished. From 1860 to 1872 as many as 58,646 Chinese coolies were imported. Lima (q.v.), the capital of Peru, is nearly in the centre of the coast region, and has a population of almost 150,000. Trujillo is the chief coast town to the north, and Arequipa to the south; there are many ports, including Callao and Mollendo. The Roman Catholic is the religion of the state, but practically (not legally) there is tolerance for dissent. Besides the university of Lima, there are lesser universities at Cuzco, Arequipa, and Trujillo, besides several state-supported high schools, and about 1870 primary schools with 105,000 enrolled pupils.

For four centuries before the Spanish Conquest under Pizarro (1532) the Incas swayed a mighty empire, under a highly civilised and centralised system of government. After the rapid conquest, there were many quarrels between the Spanish occupants and the mother-country; but the people were incessantly ground down in order to satisfy the continual demands of Spain for treasure. A great national rising in 1780 was crushed, but left the seeds of the desire for national independence, secured by the liberation wars of 1821-24. Subsequently Peru repeatedly had considerable spells of peace and prosperity. But the quarrel with Chili led to war in 1879, invasion and disastrous defeats ending in 1884 in the permanent cession of Tarapaca, the occupation (to be terminated after 10 years on a plebiscite to that effect) of Tacna and Arica, and other concessions favourable to Chili.

See works on Peru, its exploration and antiquities by Markham (1862 and 1880), Hutchinson (1873), Duffield (1877), Squier (1877), and others; the histories of the conquest by Prescott (1847; new ed. 1889), Robertson, Helps, etc.; for the war of independence, works by Stevenson, the autobiography of Lord Dundonald; for the war with Chili, Markham (on the Peruvian side, 1883).