In 1783, the Spanish claimed Batanes as part of the Philippines under the auspices of Governor-General José Basco y Vargas. The Bashi Channel was increasingly used by English East India Company ships and the Spanish authorities brought the islands under their direct administration to prevent them falling under British control. The Ivatan remained on their "idjang" castle-fortresses for some time. In 1790, Governor Guerrero decreed that Ivatans were to live in the lowlands and leave their remote "idjang". The mangpus, or indigenous Ivatan leaders, headed by the Ivatan hero Aman Dangat, revolted against the Spanish invaders. Using guns, the Spanish ended the revolution, killing various Ivatan leaders, which included the murder of Aman Dangat. Basco and Ivana were the first towns established under full Spanish control. Mahatao was then administered by Basco, while Uyugan and Sabtang, by Ivana. Itbayat was not organized until the 1850s, its coast being a ridge. Soon, Ilocanos came to the islands and integrated with the local population. Roads, ports, bridges, churches and government buildings were built in this time. Limestone technology used by the Spanish was also spread to the islands, making bridges strong and fortified. Some of these bridges still remain at Ivana and Mahatao. By 1890, many Ivatans were in Manila, and became "ilustrados", who then brought home with them the revolutionary ideas of the Katipunan. These Ivatans, who were then discontented with Spanish rule, killed the ruling General Fortea and declared the end of Spanish rule.