In the meantime, the Enryaku-ji monastery on Mt. Hiei, with its "sōhei" (warrior monks) of the Tendai school who aided the anti-Nobunaga group by helping the Azai-Asakura alliance, was an issue for Nobunaga since the monastery was so close to his base of power. In September 1571, Nobunaga preemptively attacked the Enryaku-ji monastery, then besieged Mount Hiei and razed it. In the process of making their way to the Enryaku-ji temple, Nobunaga's forces destroyed and burnt all buildings, killing monks, laymen, women, children and eliminating anyone who had previously escaped their attack. It is said that "The whole mountainside was a great slaughterhouse and the sight was one of unbearable horror." This action gained him renown as the Demon Daimyo or Devil King.