The beginnings of the coast provinces were painful and disastrous; the settlements were feeble; centuries elapsed before the natural advantages of the region were utilised, and before its accessibility and fertility drew a great immigration. The assimilation of Indian blood did not take place on a large scale, and the immigrants and their descendants became perforce horsemen and fighters. _Discovery of the Plate._--The Portuguese discovery of the east coast of South America, in 1500, was a disagreeable surprise to the Spanish government. The Treaty of Tordesillas had been framed with the purpose of giving America to Spain, while Africa and the shores of the Indian Ocean were left to Portugal. Nevertheless, the Portuguese vigorously asserted their right to the prize they had picked up by accident and insisted on the letter of the treaty. They promptly explored the coast as far south as Santa Catharina, six hundred miles north of the Plate, but they had asserted no ownership farther south at the date when the Spanish expeditions began to be sent to the South Atlantic. In 1516, a celebrated sea-captain from the north of Spain--Juan Diaz de Solis--was sent out by the Castilian government to explore the southern part of the continent. He simply reconnoitred the Brazilian coast, where the Portuguese had not yet established any settlements, and, pressing on to the south, finally reached the Plate. His first impression on rounding Cape St. Maria, where the Uruguayan shore turns to the north-west, was that he had reached the southern point of the continent and discovered the sea route into the Pacific. But the freshness of the water in the great estuary undeceived him. Following along the northern bank, he landed with a small party and was attacked and slain by a tribe of fierce and intractable Indians.