On Shigemasa's death, his incapable and tyrannous son Shigetsugu succeeded him, and popular discontent began to take a concrete form. Gradually the plan of a combination for open resistance found advocates. Among the generals on the defeated side in the battle of Sekigahara of 1600 had been one Konishi Yukinaga, an ardent believer in Christianity. After the battle his principal retainers retired to the Island of Amakusa off the coast of Hizen, among whom the most influential constantly sought means to be revenged on the Tokugawa and to promote the spread of Christianity. They found a youth named Masuda Shirō who to remarkable graces of person added a mind of great craftiness, and they presented him to the people in 1637, alleging that he was the heavenly messenger of whom Francis Xavier had spoken twenty-five years previously when leaving Japan, and who was destined to establish the supremacy of the Christian faith. They also spread rumors that the shōgun had died in Edo, and the people, much encouraged by these things, assembled in great numbers and openly offered thanksgivings to heaven. The officials in Shimabara endeavored to disperse this meeting and to arrest the leaders, but in a contest which ensued the Christians were victorious. Now the insurrection spread far and wide throughout Shimabara, Amakusa, and the neighboring districts, until the insurgents under the command of Masuda Shirō numbered over thirty thousand. At first the Edo government regarded the rebels as a mere mob of peasants, and dispatched a petty baron, Itakura Shigemasa, to restore order. But the latter's inability to cope with the trouble having afforded a gauge of its true dimensions, the commission was given to Matsudaira Nobutsuna, a powerful chief. The insurgents fought with desperate resolution and inflicted numerous defeats on the government's troops, Shigemasa himself falling in battle. But the end came at last. In 1638, the stronghold of the rebels was taken, and its defenders were either burned in the flames kindled by their own hand or put to the sword.