Although their initial objective was to cover news in the whole of the Basque Country, they actually have as their tag line Noticias de Bizkaia, as their principle market is in Biscay, where they are the second largest newspaper in the city.
Deia, together with other publications by their publishing company, was created by the Partido Nacionalista Vasco with the objective of providing news for moderates in Basque nationalist movement.
Among its early the promoters and founders were nationalists like Mitxel Unzueta, Luzio Aginagalde, Luis María Retolaza and Eli Galdós.
Among Deia's founding principles were the highlighting of timely and accurate information as well as focusing on news about individual and collective human rights, promoting solidarity of Basque society, defending Basque tradition, culture, language, politics, social life and family, alongside the promotion of the coexistence of its inhabitants within democratic institutions.
Although at an early stage Deia assumed the daily role of unifying of all current opinions that opposed the dictatorship, their lack of definition made the daily newspaper seek a closer identification with the moderate Basque nationalists, represented publicly by the Partido Nacionalista Vasco.