Asayama Nichijō (15xx-1577) was a monk in the Nichiren sect. He reported to the throne that it was his dearest wish to raise funds to cover the expenses to repair the Imperial palace that had been ruined. Emperor Gonara bestowed the name of Nichijō Shōnin upon him, or, under another view, the name of Nichijō Chōzan. He had a younger brother named Asayama Saemon, so his surname is understood to be Asayama. Owing to his consistent antagonism toward missionaries, Nichijō was called “Lucifer in the flesh” or the “Japanese anti-Christ.”
There is a lack of authenticated accounts concerning the first half of his life. According to the diary of Luís Fróis, a Jesuit missionary residing in Japan during this period, Nichijō had a wife but she sought to separate owing to poverty. He then became a soldier, participating in numerous attacks and killings. Fearful of retribution, he changed his clothes but not his customary activities. He wore dress made of lambskin, became a monk, and traveled between provinces. Nichijō planned a rebellion against the head of the Amago clan in Izumo Province and then fled to Suō Province.
Nichijō was the son of Asayama Yoshitsuna, a retainer of the Amago clan and landowner in the village of Asayama in Izumo Province. Therefore, he was likely related to the Amago clan and from Izumo Province. He also studied for a period on Mount Hiei. After arriving in Yamaguchi in Suō, he was received by the Mōri and built a small Buddhist temple. He raised money for the construction during his travels by selling Chinese-made clothing with gold brocade that he misrepresented as clothing that he received from the Emperor himself.
Thereafter, Nichijō moved to Kyōto and attempted to intervene in battles between Matsunaga Hisahide and the Miyoshi Group of Three (Miyoshi sanninshū). While intending to deliver a letter from the Mōri clan to Hisahide, he was captured by a spy from the Miyoshi. Shinohara Nagafusa, a retainer of the Miyoshi, incarcerated Nichijō in Sakai. His captors put a chain around his neck, inserted a long stick through both sleeves and attached his wrists to the stick, so he resembled a crucifix. He was given little food and kept in this state for over 100 days. However, during this period, Nichijō influenced those around him, reading Buddhist scriptures and receiving alms.
In 1568, when Oda Nobunaga marched upon the capital, the Miyoshi Group of Three fled while Nichijō was freed. His offenses were pardoned by Imperial command. In the spring, he made a palace visit and presented gifts to the Imperial Court. That summer, he gave religious lectures at the residence of Konoe Sakihisa, providing an opportunity to approach Nobunaga.
Early in 1569, Nichijō attempted to mediate a peace between Ashikaga Yoshiaki, the supreme shōgun, and the combination of Mōri Motonari and Ōtomo Yoshishige. Matsunaga Hisahide cooperated in these efforts. As a messenger of Hisahide, Nichijō headed to Kikkawa Motoharu. In the spring, Nobunaga ordered Nichijō and Murai Sadakatsu to oversee the renovation of the Imperial palace, and, by this time, Nichijō was well-known among the nobility in Kyōto.
Nichijō advised Nobunaga to expel Christian evangelists, but Nobunaga rejected his appeal after having issued a public notice several weeks earlier that permit missionaries to reside and proselytize in the capital. While Luís Fróis and Lorenzo Ryōsai visited Nobunaga, Nichijō joined for a sermon on Christianity, leading to a religious debate in front of Nobunaga. Nichijō asked questions for an hour and one-half in regard to the teachings. During this questioning, Nichijō lost his temper and attempted to draw his sword, but he was subdued. In the debate, Lorenzo inquired as to whether Nichijō had been taught by Shinkai Shōnin on Mount Hiei, and Nichijō affirmed the same. Nobunaga also asked several questions to Lorenzo.
The following day, as Nobunaga prepared to return to Gifu, Nichijō once again encouraged him to expel the missionaries, but he was rejected. Thereafter, Nichijō attempted to eliminate Wada Koremasa, a Christian, to no avail. In 1573, Nichijō fell out of favor with Nobunaga and lost his position. His descendants served as officials of the Kujō family. Asayama Irinan, a Confucian scholar, was his grandson.