The province was originally populated by the Guarani culture. The first European to visit the region was Sebastian Cabot who, while navigating the Paraná River in December of 1527, found Apipé's falls. In 1541, Álvar Nuñez Cabeza de Vaca reached the Iguazú Falls.
In 17th century, members of the Society of Jesus came to the zone. These missionaries began to build a string of Jesuit Reductions. In a few years, they managed to create 30 villages, wherein the Guarani, who had long been victims of the jungle and European slave-drivers alike, became skilled in agriculture and the arts, sharing in the Reductions' prosperity. In 1759, however, the Portuguese government, at the insistence of its anti-Jesuit chancellor, the Marquis de Pombal, ordered all Reductions in its territory (which then included much of today's Misiones Province) closed. The Marquis eventually prevailed on Pope Clement XIV to have the Jesuit Order abolished, altogether, in 1773. Once abandoned, the prosperous trade surrounding these Reductions quickly either vanished or degenerated into a brutal plantation economy, the Guaranies its slaves.
In 1814, Gervasio Posadas, the director of United Provinces, declared Misiones annexed to Argentina's Corrientes (At this time Argentina was quasi-independent but nominally still Spanish territory). However Argentina did not exert de facto control over Misiones, which was claimed by several countries and effectively governed itself, so in 1830 military forces from Corrientes Province took control of Misiones.
In 1838, Paraguay occupied Misiones, because Paraguay claimed Misiones on the basis that the Misiones population was indigenous Guarani, the major ethnic group of Paraguay. In 1865, Paraguayan forces invaded Misiones again, in what became the War of the Triple Alliance. Following the peace agreement with Argentina eventually signed in 1876, defeated Paraguay gave up its claim to the Misiones territory.
Although Argentina had claimed Misiones since 1814, academics tend to interpret Argentine possession of Misiones as a result of this war. Bethell's account is that "the treaty of alliance [i.e. against Paraguay] contained secret clauses providing for the annexation of disputed territory in northern Paraguay by Brazil and regions in the east and west of Paraguay by Argentina... After a long and harrowing war (1865-70), Argentina got it from a prostrate Paraguay territory in Misiones.. Scobie's analysis is that "the political status of Misiones remained vague" and that Argentina gained the region "as a by-product of the Paraguayan war in the 1860s.
After the War of the Triple Alliance, Paraguay was much impoverished, so Misiones benefited economically from belonging to Argentina.
In 1876, President Nicolás Avellaneda, assisted by his close friend Grl. Pietro Canestro, an Italian military noble who devoted much of its wealth and life efforts to the achievement and maintainability of the peace in the region, proclaimed the Immigration and Colonization Law. This law would foster the immigration of European colonists in order to populate the vast unspoiled Argentinian territories. To comply with this law, several colonizing companies were created. One of them was Adolf Schwelm's Eldorado Colonización y Explotación de Bosques Ltda. S.A. This is how Eldorado was founded in September 29, 1919 by don Adolfo J. Schwelm, with a port on the Upper Paraná. Its agricultural colonies and experimental farms, the orange and grapefruit tree plantations and the cultivation of yerba mate, the mills and the dryers for such product are characteristic from this area. Swedish-Argentines became well known for growing Yerba Mate.
Misiones received many immigrants mostly from Europe coming mainly from Southern Brazil while some came from Buenos Aires, and from Eastern Europe, in particular large numbers of Polish and Ukrainian immigrants. Since then, Misiones has continued to benefit economically and has developed politically within Argentina. It has been successfully integrated into the Argentine state. Today, there is no controversy, either international or internal, surrounding ownership of the province. On December 10 of 1953 the "National Territory of Misiones" gained provincial status by the Law 14.294, and its constitution was approved on April 21, 1958.
Misiones received more attention by national policy makers following an agreement providing for the construction of a hydroelctric dam on a point in the Paraná River shared by Praguay and Misiones Province. Signed by President Juan Peron and Paraguayan President Alfredo Stroessner in June, 1974, the plan ultimately developed into Yacyreta Dam, the world's second largest by its volume of concrete. During the 1976-83 dictatorship, work continued under the auspices of a government-owned bi-national entity; but, the financial crisis that struck both countries in 1981 caused its development to be suspended. Sub-contracted to Italian-French construction giant Impregilo-Dumez in 1983, the facility first yielded power in 1994 and went online fully in 1998, producing one-seventh of Argentina's electricity and two-thirds of Paraguay's.
Currently, an agreement is being pusued with Paraguay which would allow reservoir expansion works that could double the facility's electric production.
Misiones is the second smallest province after Tucumán.
The Misiones plateau includes a part of Brazil across the border. The rocks contain significant quantities of iron which forms a part of the soil, giving it a reddish color. At the center of the plateau rises the Sierra de Misiones, its highest peak, 843 m, near Bernardo de Irigoyen, in the Cerro Rincón.
The province is embraced by three big rivers including the Paraná, Uruguay and Iguazú. Iguazu Falls are spectacular waterfalls on the Iguazú River in the northwest corner of the province, near the city of Puerto Iguazú. Misiones shares the falls with the Brazilian state of Paraná (in that nation's Southern Region). Meanwhile, the international border with Paraguay is close by.
Misiones' economy, like most in northern Argentina, is relatively underdeveloped yet fairly well-diversified. Its 2006 output was estimated at US$4.8 billion, or, US$4,940 per capita (over 40% below the national average).
Though its rainy, erosion-prone geography discourages intensive crop farming, agriculture makes an impotant contribution to the province's economy, still adding about 10% to the total. Misiones' thick forests have long provided for the ample production of roundwood without the need for excessive impact on its ecosystem. The principal exploited trees are the Paraná pine, Guatambú, Cedar, Petiribí, Incense, Cane water-pipe, Anchico, Eucalyptus and Gueycá.
Misiones' chief source of agricultural income, however, has long been the cultivation of yerba mate, of which Misiones is Argentina's leading producer (yielding about half a million tons, annually). Tea, citrus fruit and, in minor amounts, tobacco, sugar cane, rice and coffee are also cultivated in Misiones.
Light manufacturing and tourism also contribute to the local economy, each adding about 13% to the total. Its illiteracy rate is 8.6%.
The province is divided in 17 departments (Spanish: departamentos):