 On that year, the Spanish launched a massive campaign to occupy Jolo.Spurred by the need to curb slave raiding once and for all and worried about the presence of other Western powers in the south (the British had established trading centers in Jolo by the 19th century, and the French were offering to purchase Basilan Island from the cash-strapped government in Madrid), the Spanish made a final bid to consolidate their rule in this southern frontier.On 21 February of that year, the Spaniards assembled the largest contingent against Jolo, consisting of 9,000 soldiers, in 11 transports, 11 gunboats, and 11 steamboats.