Includes correspondence, missives, orders, and miscellaneous notes concerning American involvement in the abortive López Expedition of 1851 and its aftermath, in which the Spanish South American defector Narciso López attempted to mount a military filibuster to remove Cuba from Spanish control and bring it into the United States as a slave state. These materials include some materials of Americans before the raid, expressing hopes that an American slave state of Cuba could offset the admission of California as a free state, as well as a military order by U.S. Naval Secretary William A. Graham to send the steamer John Hancock to New Orleans to prevent support to the López Expedition in the wake of its failure. Spanish royal orders to destroy the Filibuster, as well as indications of its subsequent flight to Nicaragua, are also included. Also in this file is a copy of a death certificate for Cuban-American Pedro Ángel Castellón signed by Severín LaTorre, Spanish consul to New Orleans, and verified in 1867. The folder includes a military promotion request for Leopoldo García Gardó signed by Antonio Venenc y Andrada in Segovia, Spain. The relationship of the latter two items with the other filibuster material is unclear. Partial geographical list: New York City, Havana/Habana (Cuba), Matanzas (Cuba), London (England), Tampa (Fla.), Key West, Jackson (Miss.), Augusta (Miss.), New Orleans (La.), Centreville (La.), Cheshire (Mass.), St. Augustine (Fla.), Madrid (Spain), Segovia (Spain). Additional keywords: Seminole War, Zachary Taylor, Franklin Pierce, California, Slavery, Caribbean, Georgia, Navy Department, Queen Isabella/Isabela II, U.S.-Spain relations, Spanish Army.