In November of 1274, Mongol forces landed on the Japanese coast in what history calls the Battle of Bun'ei, the first of two invasion attempts that would test Japan's defenses and its sense of divine protection alike. Word of the attack reached Nichiren, by then living in a period of relative isolation after years of confrontation with Japan's religious and political establishment, and on the first day of December, weeks after the invasion, he sat down and inscribed a mandala. He had inscribed such mandalas before and would go on inscribing them for the rest of his life, but this one carries a term he used nowhere else in his surviving autographed work: Dai Honzon, Great Object of Worship.
Reading the timing and the wording together, the mandala looks like a considered response to a national crisis rather than a routine devotional exercise, an assertion, made in ink at a moment of real danger, of what Nichiren believed the country's protection actually depended on. He also inscribed it with his kao, a personal written seal that functioned across East Asia the way a formal signature does, marking the document as unmistakably his own rather than a disciple's copy. Entrusted afterward to his disciple Nikko and passed down through Nikko's own student, the mandala has been held at Hota Myohonji, the temple that student founded, ever since.