Rui Gomes da Silva, 1st Prince of Éboli

Dom Rui Gomes da Silva (in Spanish, Ruy Gómez de Silva), 1st Prince of Eboli (Chamusca; 27 October 1516 – Madrid; 29 July 1573), was a Portuguese noble and one of King Philip II of Spain's main advisers.

Rui Gomes da Silva was born in Chamusca, Portugal and was the second son of Dom Francisco da Silva, Lord of Ulme and Chamusca. In March 1526, he escorted Infanta Isabel of Portugal to Seville where she married Charles I of Spain.

He remained in Spain living within Isabel's entourage. In 1527, when Philip II of Spain was born, Rui became his page. An enormous friendship linked the two boys during their entire lives. In 1554 when his eldest brother John died, Rui inherited the lordship of Ulme and Chamusca.

When Philip inherited the Spanish throne in 1556, as Philip II, Rui, who had been close to one of the more influential ministers, received several honors, among them, prince of Éboli and Sumiller de Corps to the King. As a minister of Philip II, Rui Gomes da Silva had a remarkable importance within the Spanish politics, and Philip II granted him the highest nobility title, Grandee of Spain.

Due to his influence in the Spanish Court, Rui was known among foreign ambassadors as "Rey Gomes II " (King Gomes), instead of his Hispanicized name "Ruy Gomes". His biggest political adversary was Fernando Álvarez de Toledo, 3rd Duke of Alba. They had differing views concerning Spain's government. The Duke of Pastrana defended a much more federalist and compromise-oriented system, while the Duke of Alba was for the centralization of the power within a unified and martial monarchy.