In the mean time, the two friars and the Moor penetrated a considerable distance into the interior of the continent, and sent home glowing accounts of rich and delightful countries which they said they had discovered. The inhabitants had, at first, been hostile, and had killed the Moor; but in the end submitted to the authority of the King of Spain. Mendoza, believing the accounts of the friars to be strictly true, prepared an expedition for the conquest of the countries they described. Disputes with the different Spanish chieftains occupied some months, at the end of which Cortes returned to Spain, in disgust. Mendoza despatched two bodies of troops, one by land, the other by sea, to reconnoitre the newly discovered land, and clear the way for conquest. The marine expedition was undertaken by two ships, under the command of Fernando de Alarcon, who sailed from Santiago on the 9th of May, 1540, and proceeding north-west along the coast, he reached the head of the California Gulf, in August of the same year. There he discovered the river now called the Colorado. The stream was ascended to the distance of eighty leagues, by Alarcon and some of his men, in boats; but all their inquiries were unsatisfactorily answered, and it was determined to return to Mexico. The vessels returned safely before the end of the year.
The land forces sent, at the same time, to the north-west, were composed of infantry and cavalry, and commanded by Francisco Vasquez de Coronado, who had been appointed governor of New Gallicia, in place of Nuno de Guzman. The party left Culiacan on the 22d of April, 1540, and took their way north, following the course described by the friars. They found the route which had been represented as easy, almost impassable. They made their way over mountains, and deserts, and rivers, and, in July, they reached the country called Cibola by the natives, but found it a half cultivated region, thinly inhabited by a people destitute of the wealth and civilization they had been represented as possessing. What had been represented as seven great cities, were seven small towns, rudely built. A few turquoises and some gold and silver supposed to be good, constituted the amount of what had been termed immense quantities of jewels, gold and silver. The Spaniards took possession of the country and wanted to remain and settle there. But Vasquez refused to acquiesce; and after naming one of the towns he visited, Granada, he started for the north-west, in search of other countries. The region called Cibola by the inhabitants, which Vasquez visited, is the territory now called Sonora, and is situated about the head waters of the Rivers Yaqui and Gila, east of the upper portion of the Gulf of California. The movements of the Spaniards after leaving Cibola, in August, 1540, have been the subject of very vague and contradictory accounts. All that is certain is, that the greater part of the force soon returned to Mexico, and that Vasquez, with the remainder, wandered through the interior for nearly two years longer, when, being disappointed in his expectations, he returned to Mexico in 1542.