Fernando de Alencastre Noroña y Silva, 1st Duke of Linares, GE (April 15, 1662 in Madrid, Spain – June 3, 1717 in Mexico City) was a Spanish nobleman and military officer.

In addition to the two titles he inherited, he was knight commander of the Order of Santiago, lord of the bedchamber of the king, and lieutenant general in the army.

He was also knight commander of the royal arms in the Kingdom of Naples, honorary viceroy of Sardinia, and vicar general of La Toscana.

Alencastre ordered the construction of four well-armed, light warships at Coatzacoalcos to reinforce the Armada de Barlovento (coast guard).

Spain had supplied Peru by bringing goods by government fleet to the Atlantic port of Portobelo in Panama, from whence they were carted to Lima overland.

In their place, the French were sailing from Saint Malo in France, around South America's Cape Horn, to the seaport of Callao in Peru.

Viceroy Alencastre suggested that Spain permit private Spanish merchant ships to sail between the Pacific ports of Acapulco and Callao.

Another foreign policy issue between Spain and Britain during Alencastre's tenure as viceroy was the existence of a British colony at Laguna de Términos, whose colonists harvested tropical timber, in particular logwood trees, and exported them to American and European markets in violation of Spanish law.

[citation needed] The pueblo of San Felipe de Linares was founded by Sebastián Villegas Cumplido in September 1711, and named in honor of the Viceroy.

The indigenous and sophisticated Pueblo peoples continued in revolt against the occupation of their homeland, taken by the Spanish in 1598 as the Province of Santa Fe de Nuevo México.

He prohibited the manufacture of the alcoholic beverage aguardiente from sugar cane, and made attempts to suppress immorality among the regular clergy.