 When the French under Admiral Cécille blockaded Basilan in 1844–45, an island which they called Taguime, intent on establishing a network of naval stations to protect French trade in the area, the Spanish governor protested that Basilan had recognized Spain's sovereignty just the year before, in February 1844.The French then forced the Basilan datus to sign a document affirming the “absolute independence of Basilan vis-a-vis Spain” on January 13, 1845, aboard the steamer "Archimede".On February 20, 1845, France forced the Sulu Sultan to formally cede Basilan Island to France in exchange for 100,000 piastres or 500,000 French francs.