Immediately after the victory, the Guaranis were set by the Spanish to assist in the construction of the new town, which was to be the head-quarters of the Imperial power in the south-east of the Continent.  Once definitely settled here, the conquistadores set themselves to extend the frontiers of their dominions, which in the first place were confined to the neighbourhood of the new town of Asuncion itself.

The tribes in the immediate neighbourhood were now more than merely friendly:  they were actively servile.  But the case was different with the other native peoples, more especially with the Indians in the Chaco, the wooded and swampy district on the opposite side of the river.  These showed themselves fiercely inimical to the new-comers, and it was seldom that the Spaniards were without a feud of some kind to suffer at their hands.

The new colonists had now time to look about them.  Much had happened since they had first landed on the shores of the River Plate, but the main object of the expedition still remained clear to them.  This was the discovery of a road from the south-east to Peru.  Ayolas determined to take up this fascinating quest in person.  Accompanied by a number of men, he sailed up the river until he came to a spot at which he judged that an attempt at the overland journey might well be attempted.  Leaving Domingo Martinez de Irala, his lieutenant, in charge of the ships and of a force of men, Ayolas marched into the forest and disappeared into the unknown.  It was his fate never to return.  His company, ambushed and cut up by a tribe of hostile Indians, perished to a man.

It was months before Irala learned of the catastrophe.  In the belief that his chief was still in the land of the living, he waited with his ships and men at the point where Ayolas had disembarked, varying his vigil from time to time by a cruise down-stream in search of provisions.  The news came to him at length, shouted out by hoarse defiant voices from the recesses of the forest on the banks.  For a while the Spaniards would not believe the surly message of death given by the unseen Indians.  In the end, however, its truth could not be doubted, and Irala assumed command of the party.  Returning to Asuncion, he was unanimously appointed Governor by the settlers of the place.

[Illustration:  SUGAR-MAKING.

A seventeenth-century representation of the whole of the processes of the manufacture of sugar.

From “Historia Antipodum."]

The character of Domingo Martinez de Irala was eminently suited to the post he now held.  His courage was high, his determination inflexible, and his energy abundant.  It is true that, in the same manner as his colleagues of the period, he was frequently totally careless of the means employed so long as the end was achieved.  Nevertheless, he was in many respects an ideal leader, and his vigorous personality kept in check both the ambitions of the Spanish cliques and the dissatisfaction of the less friendly Indians.