He was the third Marquis of Vilagarcía de Arousa and was the first Galician viceroy nominated by the Bourbon for an American viceroyalty (Perú). In 1730, when he was seventy, he took up his post as viceroy of Peru in Lima. One of his main tasks was the defence of the ports of Peru against the attacks of the English during the war from 1739to 1748. In 1746, he was relieved of his post and replaced by the general captain of Chile.