In 1869 it was estimated that there were 10,000 Protestants among the English, Scotch, American, and German settlers. - The mouth of the Rio de la Plata was discovered in 1512 by Juan Diaz de Solis; and as early as 1535 Don Pedro de Mendoza began the settlement at Buenos Ayres, while the country as for N. as the site of Asuncion, the present capital of Paraguay, was explored by parties under his orders. Many colonies were founded in that century, and much progress was made in the civilization of the Indians under Don Juan de Garay, who was in 1580 appointed lieutenant governor of those provinces, which were then regarded as forming a part of the viceroyalty of Peru. In 1620 a new government was formed, having for its capital Buenos Ayres, hitherto dependent upon the government of Paraguay, and both continued under the viceroyalty of Peru till 1776, when the viceroyalty of Buenos Ayres was created, comprising the territories now known as Bolivia, Paraguay, Uruguay, and the Argentine Republic. In 1806 Buenos Ayres and Montevideo were captured by a small British force, which, however, was soon compelled by the bravery of the inhabitants to relinquish the conquest.

An attempt was made in August, 1807, by a British army 10,000 strong, to reconquer the city of Buenos Ayres; but the invaders were defeated. Gen. Whitelock, who commanded the attack, was on his return to England cashiered for incapacity. The struggle for independence was begun about three years later, and was waged on both banks of the Plata, until the only remaining Spanish forces surrendered in Montevideo in 1812. During this period the war of independence was also going on in Upper Peru (Bolivia) with varied results, and in the adjacent provinces, the Spaniards suffering considerable reverses in Salta and Tucuman. In January, 1813, the chief power was vested in the "Sovereign Assembly" formed in Tucu-man, then the seat of government. About the same time Gen. Jose de San Martin, the governor of the province of Mendoza, conceived the project of crossing the Andes for the purpose of driving the Spaniards out of Chili. The enterprise proved successful, and Chili was freed after the memorable battles of Cha-cabuco and Maipti (1817-18). Immediately afterward the Chilians and Argentines carried their united arms into Peru, and entered Lima in 1821. The Portuguese in 1816, under pretext of putting down anarchical movements set on foot in Uruguay by Artigas, descended into that territory and took possession of Montevideo, in spite of the protests of the Argentine government, then too busily engaged in preserving order at home and in carrying on the war of independence, to enter openly into hostilities against the invaders.

The same year the independence of the United Provinces of La Plata was declared in Tucuman (July 9), in which city, after the dissolution of the sov-ereign assembly, a congress had assembled March 26, 1817, and promulgated a provisional constitution, Gen. Puyerredon being named supreme dictator. The seat of congress was afterward removed to Buenos Ayres, in the hope of securing greater liberty of action; but in 1820 the directory fell, and in the following year a democratic form of government was established. The administration was composed of Gen. Rodriguez and two secretaries, Don Bernardino Rivadavia and Don Manuel Garcia. The riverine provinces soon united themselves with Buenos Ayres, and this alliance led in 1824 to the organization of the republic, under the administration of Las Heras. Brazil forced the United Provinces into a declaration of war, and blockaded the city of Buenos Ayres, January, 1826; and, though the Argentine arms were for a time victorious by sea and land, the event served to prove the weakness of the union. It is important to remember that the size of the different provinces was extremely various, and that the character and interests of the population were no less varied.

It may also be added that the difficulty of establishing communication between the provinces rendered useless at times prudent measures taken by the central government. There was almost a feudal aristocracy in the north; in the wide ranges of the pastures the herdsmen felt and exercised a rude power; but there was a greater degree of moderation in the agricultural states. Buenos Ayres, as the only seaboard state, and as much the richest, naturally took the lead, both in preparing the way for independence and in forming the confederacy. The higher classes possessed immense landed and other property. Many of them had been educated in Europe, and had introduced into South America the refinements of a high civilization, and hoped to extend those refinements over the whole country by means of a form of government. But under their ideas this government was to be wielded by the rich and educated classes. Their party, the Unitarios, succeeded in framing the constitution of 1825, under which the nation was represented by a small aristocracy. Rivadavia was the first and only president of the confederation under this constitution.

The greater part of the large province of Buenos Ayres took its political bias from the independent and republican tone of the cattle drivers and herdsmen, who knew their power, and were not averse to asserting it. They soon found a leader in Juan Manuel de Rosas, who was descended from a noble family of Spain. Untutored in the arts of refinement, and at once daring in the highest degree, ambitious, and cunning, he soon found numerous supporters among the masses of the people, and especially after he had succeeded in extending the limits of the province of Buenos Ayres, by subduing the savages of the pampas and other indigenous tribes, who were implacable enemies of the gauchos or herdsmen. No sooner had he espoused the cause of the federalists than his popularity spread to the provinces, and he gained the sympathies of many prominent personages who regarded with a jealous eye the recent excesses of military power. He had opposed the Unitarios at the time of the union, although unsuccessfully; but by 1827 he had acquired sufficient influence, and found himself certain of the aid of other popular chieftains, such as Bustos, governor of Cordoba, Ibarra, commandant of Santiago, Quiroga, of La Rioja, and Lopez, of Santa Fe. They protested against the constitution and government of 1825, and took up arms in force in support of their protest.