Francisco de Llanos was a career officer of the Armada de Barlovento in the late seventeenth century. In September 1685 he was captain of the armada's 335-ton frigate La Honhon, when the fleet engaged French pirates fresh from the rape of Campeche. The armada captured defectors from the La Salle expedition who disclosed the French plan to plant a colony near the mouth of a large river (the Mississippi) that René Robert Cavelier, Sieur de La Salle, had descended from Canada in 1682. The fleet failed to pursue and capture the hated pirate leader Laurens de Graff, and for that Llanos and several other officers of the armada were disciplined. Llanos was suspended from duty for two years, after which he was restored to duty as capitán de mar y guerra and given command of the frigate Nuestra Señora de la Encarnación. In 1690 he conducted the Llanos-Cárdenas expedition to Espíritu Santo (San Bernardo or Matagorda) Bay on the Texas coast.