PACHECO y OSORIO, Rodrigo (pah-tchay'-co), Marquis of Cerralvo, viceroy of Mexico, born in Spain in the last quarter of the 16th century; died in Valladolid about 1650. When the court at Madrid received notice of the deposition by a popular rising, on 15 January, 1624, of the viceroy, the Marquis de Golves, Pacheco, possessing the full confidence of King Philip IV. and his ministers, on account of his energy, was sent out in haste, and took charge of the government, 3 November, 1624. He soon gained the affection of the Mexicans by his moderation and humanity, and took measures to protect Acapulco against the repeated attacks by Dutch fleets under Prince Nassau and Admiral Spilberg. In 1627 the city of Mexico suffered a partial inundation, and measures were taken to repair the dikes, but they were soon neglected, and in 1629 the river Aculhuacan burst them, and the lagoons rose, so that for more than a year there was nearly six feet of water in the streets, and nearly 30,000 natives perished. It was resolved to move the city to the hills of Tacubaya, but, on account of the expense, the project was abandoned, and in 1630 the proposal of Enrique Martinez (q. v.) was accepted, and the drainage-canal of Huehuetoca was begun. In 1628 the treasure fleet of thirty-one vessels, carrying $12,000,000 to Spain, was captured by the Dutch admiral, Piet Hein (q. v.). In 1635, as the Indians near the Rio Grande became troublesome again, the viceroy ordered a fort to be constructed in the province of New Leon, which was named Cerralvo, after him, and is now a thriving town. Pacheco had repeatedly resigned on account of his health, and in September, 1635, he was relieved by the Marquis de Cadereita, and soon afterward returned with great riches to Spain.