He was the son of José María Gil-Robles y Quiñones, leader of the CEDA and a prominent figure in the period leading up to the Spanish Civil War, and Carmen Gil-Delgado Armada.

Thus, he was grandson of Carlist theorist Enrique Gil Robles and brother of Álvaro Gil-Robles, who was the second Ombudsman of Spain between 1988 and 1993.

[2] was also editor of the "Boletín de Legislación extranjera" (Foreign Legislation Bulletin) and between 1959 and 1964 he was a professor of Political Law at the Complutense University of Madrid.

[2] In 1989, and after the re-foundation of People's Party, Marcelino Oreja asked Gil-Robles to accompany him in the candidacy for the 1989 European Parliament election.

[2] In January of that year he was elected President of the European Parliament after obtaining a large majority of 338 votes,[4] office he held until 1999.