For most of the twentieth century the school was known abroad through a lay organisation rather than through its own priesthood. Soka Gakkai was founded in 1930 as a society of educators affiliated with Nichiren Shoshu, was suppressed during the war, and after 1945 grew into one of the largest religious movements in Japan through a vigorous programme of household conversion. Its members were formally lay believers of Nichiren Shoshu, and the temple provided the priests, the ordinations and the objects of devotion.
The relationship broke down at the end of the 1980s over authority: what a lay organisation may do without priestly sanction, how the teaching may be presented, and where the leadership of the movement lies. In 1991 the priesthood terminated the affiliation and the members of the lay organisation were excommunicated as a body. Each side has published its own account, and the atlas records that the two accounts differ rather than choosing between them.
The consequences were structural. Soka Gakkai continued as an independent lay Buddhist movement with millions of members and now confers its own object of devotion. Nichiren Shoshu retained its temples, its priesthood and its head temple, and a considerably smaller membership, which it has since rebuilt through its own lay associations. Neither is the whole of Nichiren Buddhism, which also includes the larger Nichiren Shu and other schools with their own head temples.