He did his bachillerato (secondary school) studies in the Instituto Xeral e Técnico (General and Technical Institute) in the city of Lugo, where he befriended the writers Evaristo Correa Calderón and Ánxel Fole.

During his time in Santiago, he regularly attended the literary gatherings at the Café Español, and his friends included Francisco Fernández del Riego, Domingo García Sabell, Gonzalo Torrente Ballester, Ricardo Carballo Calero, Carlos Maside, and Xosé Eiroa.

The military uprising of July 1936 found Cunqueiro in Mondoñedo, and thanks to the influence of his conservative family, he was not subjected to reprisals, and was able to find work as a teacher in a private school in Ortigueira from October 1936 onwards.

He was also a subdirector for Vértice, a publication of the National Delegation of Press and Propaganda, in which he published "The Story of the Knight Rafael" (1939), his first fiction in Spanish.

He was a multifaceted writer, and his extensive literary output extends into the fields of journalism, poetry, narrative prose, and theater, not to mention his work as a translator.

During the 1940s and 50s, he began to dedicate himself primarily to narrative and journalism, publishing three important novels: Merlín e familia e outras historias, As crónicas do sochantre and Se o vello Simbad volvese ás illas.

Cunqueiro was the source of the famous quote Mil primaveras máis para a lingua galega ("A thousand more springs for the Galician language").