The word "Tinguian" may have been derived from the Malay word "tinggi," which means mountain or highlands, and may have been coined during the early Spanish period. As used by the Spanish colonizers, the word used to refer to all mountain people or hill tribes in the entire archipelago, living in places such as Zambales, Bohol, Basilan, and Mindanao. It was only later that the term was used exclusively for the mountain-dwelling people of Abra, Ilocos Sur, and Ilocos Norte.
The term "Itneg" has come to be used synonymously with "Tinguian." The word, according to one interpretation, is derived from "iti uneg," which literally means "the interior." Or it could have been derived from the combination of the prefix "I-," which indicates a place of origin, and the name of a major river and geographical area, "Tineg." The Tinguian have always thought of themselves and the other highland dwellers of the Cordilleras as Itneg, people of the interior uplands. There is a tendency, however, to refer to the inhabitants of Abra's isolated hinterlands as Itneg and to the province's more acculturated population as Tinguian, especially since the latter are supposedly hardly distinguishable from the lowland Ilocano.
Today, there are two identifiable Tinguian groups, namely, the "valley Tinguian" and the "mountain Tinguian." The first occupy the village communities where there are also Ilocano settlers, while the second are distributed in sparsely populated areas in the highland country of northern and eastern Abra.
The region covered by the original Tinguian population is significant. Azurin (1991) has echoed the earlier contention of the anthropologist Cole that certain pueblos in the Ilocos region "recognized as Ilocano are but Christianized Tinguian." The ancestral domain of the Tinguian covers a mountainous region which has four valleys and four river systems joining up with the Abra River, which empties into the China Sea. It is significant to note that the Spaniards used synonymous terms in referring to the highland dwellers of Abra (the Tinguian), and of the mountain provinces. The latter became known as the Ygorotes or "people from the mountain range". Tinguian territory is bounded on the North by the Ilocos Norte, on the West by Ilocos Sur, on the South by Bangued, and on the East by Kalinga-Apayao. The Tinguian are mainly in the towns of Tubo, San Quintin, Luba, and Buliney in Abra (Peralta 1988:13). They number around 57,000.