Etymologically, it is usually considered that "Boal" comes either from the Indo-european languages, *bod- (stream, ditch), or from the Latin, bove or *bovale (ox).

Although some authors believe that "Boal" could be understood as the expression of an old anthroponym or person name, Bovali (iler) or Baudiliu (adducing the form Baudali), it is common to consider its original meaning either as "terreno frecuentado y apropiado para el pasto del ganado vacuno" ("land frequented and appropriate for the grazing of cattle") or as "corral de bueyes o dehesa boyal" ("corral for oxen or ox pasture").

Likewise, dolmens near Llaviada (nowadays disappeared) are supposed to date from this time, together with the oscillating granitic mass known as Penedo Aballón (located near Penouta, and knocked down in 2004, probably by a few vandals).

From the Bronze Age (approximately 1500-1100 b.C) are believed to date the anthropomorphic paintings (both masculine and feminine) found in the Cova del Demo ("Cave of Devil" in English), located near the hamlet of Froseira, in the civil parish of Doiras.

All the preceding facts, together with the signals of mining work devoted to the extraction of metals and, especially the Celtic fortifications of Pendia, Los Mazos and La Escrita also prove the aforementioned pre-Roman settlements.

After about four centuries of Roman domination, the barbarians entered the Iberian Peninsula, and Suebi settled down in the western area of Asturias, reaching their maximum expansion about the year 450.

The fights between the bishops of Oviedo and Lugo for the territories located between the rivers Navia and Eo came to an end by means of an agreement promoted by the king Alfonso VII.

The definitive independence of Boal as a municipality took place in 1584, when representatives of the inhabitants of its parishes met, drawing up the first local regulations and agreeing on the way to choose the offices of town councilors, mayor, constables, attorneys, etc.

Furthermore, in July 1823 noticeable damages were caused by a group of about 24 robbers commanded by Miguel Álvarez Samartino de la Trapa, who stole money from the taxes income and tore documents of the municipal secretary’s office.

In connection with this, it is worth mentioning the uprising that took place in 1895, in which the forgers of the municipality destroyed all the machines for making tacks that Víctor Sánchez, a local businessman, was installing in the village of Armal with the aim to start a strong tacking industry able to face the great external competition, especially that English one, which finally made unfeasible the traditional means of working iron in the municipality.

In addition, the money furnished by many emigrants contributed decisively to the construction of various schools in several villages of the municipality and the elementary school of the capital town, known as "Las Graduadas", in 1934, which was promoted by the "Sociedad de Instrucción Naturales del Concejo de Boal" ("Association for the Education Natives of the Municipality of Boal") in La Habana (Cuba).

The decadence of tungsten mining, which had employed up to 254 workers, and the end of the construction of the big reservoirs along the Navia River, together with the gradual abandonment of cattle farming (still at present the main economic activity of the municipality) led to new migratory flows, especially from the 1950s on, but in this case they were directed preferentially to other regions of Spain (the industrialized center of Asturias, Madrid, etc.)

The relatively high levels of population remained until 1960, not just because of the dam but also because of the tungsten mining near Penouta and because of the existence of traditional agriculture requiring a lot of labor.

By the middle of the 20th century emigration started again and strongly, but this time it was directed to different destinations: to the centre of Europe, France, Germany, and also to the main industrial towns and cities of Asturias, especially Gijón and Avilés, etc.

Although the percentage of workers is clearly a majority in the service sector (see table), its weight is quite lower than the regional mean, and it is not crazy to state that still at present, economy in Boal is based to a large extent on cattle farming, which employs almost one third of the working population, and is mainly destined to milk production, being Boal the main producer among the western municipalities in Asturias.

In this mainly agricultural and farming municipality we can taste infinity of natural products, among which it is worth mentioning its excellent vegetables, beans and the great quality potatoes.

Game constitutes another important chapter in Boal’s cooking, being frequent pieces such as roe deer and wild boar, apart from partridge, Eurasian woodcock and hare.

Moreover, honey has a huge variety of applications on the local cooking, which is not surprising taking into account that it is a typical product in the municipality having widely recognized quality.

We can also find different architectural examples: palaces, large houses and churches, among which it is worth mentioning the following: The municipality of Boal hosts a great number of festivities and fairs.