Fogs and cold rains are not uncommon during the wet season, while one or more typhoons can be expected each year.  Earthquakes are likewise of occasional occurrence, but the construction of the houses is such that storms and earthquakes do much less damage than along the coast.

There is no doubt that the natural ruggedness of the country and the long rainy season have had a strong influence on the people, but this has been chiefly in isolating them in small groups.  The high mountains separating the narrow valleys, the lack of water transportation, the difficulty of maintaining trails, have all tended to keep the people in small communities, while the practice of head-hunting has likewise raised a barrier to free communication.  Thus, the settlements within a limited area have become self-sustaining groups; a condition which has existed long enough to allow for the development of five dialects.

The traditions of the Tinguian furnish us with no stories of an earlier home than Luzon, but there are many accounts of migrations from the coast back into the mountains, after the arrival of the Spaniards and the Christianization of the Ilocano.  The fact that there is an historical background for these tales is amply proven by fragments of pottery and the like, which the writer has recovered from the reported sites of ancient settlements.

The part played by this people in Philippine history is small indeed, and most of the references to them have been of an incidental nature.

Apparently, they first came in contact with the Spanish in 1572 when Salcedo was entrusted with the task of subduing that part of Luzon now known as the Ilocano provinces.  The people he encountered are described as being more barbarous than the Tagalog, not so light complexioned, nor so well clad, but husbandmen who possessed large fields, and whose land abounded in rice and cotton.

Their villages were of considerable size, and each was ruled over by a local headman who owed allegiance to no central authority, There was a uniform, well recognized code of law or custom, and a considerable part of the population could read and write in a native script similar to that of the Tagalog.  They also possessed gold, which was reported to have come from rich mines in the interior, and on primitive forges were turning out excellent steel weapons, but the use of fire-arms was unknown.  According to Reyes, their weapons consisted of lances, bows and arrows, bolos, great shields which protected them from head to foot, blow guns and poisoned arrows.  The newcomers also found a flourishing trade being carried on with Manila and the settlements in Pangasinan, as well as with the Chinese.  This trade was of such importance that, as early as 1580 pirate fleets from Japan frequently scoured the coast in search of Chinese vessels and goods, while from time to time Japanese traders visited the Ilocos ports.

Apparently trade relations were not interrupted for a considerable time after the arrival of the Spaniards, for in 1629 Medina states that ships from China, Macao, and India “are accustomed to anchor in these ports—­and all to the advantage of this district.” [8]