He governed as a tenente Trastámara, Faro (A Coruña), Viseu, and Seia,[4] owned vast estates in his native land, and was a generous patron of religious institutions.

On 29 July 1118, Queen Urraca, with the consent of her son Alfonso, returned to Bermudo and to his brother Fernando the territories belonging to the monastery at Sobrado which King Ferdinand I had taken by force in 1050.

[10] After the death of Theresa, Countess of Portugal, on 11 November 1130, he participated in the uprising from his castle in Seia, although his brother-in-law, King Afonso Henriques, forced him to desist and Bermudo returned to Galicia, rarely crossing the Minho River thereafter.

[13] The monastery, now in ruins with only the church of San Pelayo de Genrozo standing, was situated in the territory of Nendos, in a small village known as Las Cascas, close to the city of Betanzos.

He and his brother Fernando made many donations to the monastery at Sobrado, which had been founded by their ancestors, and owned all its estates over a period of 24 years, from 1118 until 11 January 1142 when they voluntarily handed it over to the Cistercian monks.

Years later, in 1150, Urraca made a donation of several properties to the newly founded establishment under the condition that she and four female relatives were to be accepted as members of the religious community of this convent which was called Santa María de Nogueirosa.