Tiandihui

thumb|Hongmen seal, 19th century Amoy thumb|Hongmen seal, 19th century Guangdong The Hongmen (Vast Family), formerly Tiandihui (Heaven and Earth Society), is a Chinese fraternal organisation and historically a secretive folk religious sect in the vein of the Ming loyalist and anti-Qing White Lotus Sect, the Tiandihui's ancestral organisation. As the Tiandihui spread through different Chinese counties and provinces, it branched off into many groups and became known by many names, including the Sanhehui. The Hongmen grouping is today more or less synonymous with the whole Tiandihui concept, although the title "Hongmen" is also claimed by some criminal groups. Its current iteration is purely secular.

During the 19th century, branches of the Hongmen were formed by members of the Chinese diaspora in the United States, Canada and Australia, where they became known as "Chinese Freemasons." Following the collapse of the Qing dynasty in 1911 as a result of the Xinhai Revolution, the Hongmen's central purpose no longer existed, resulted in a divergence among its members, some of whom turned to crime. In modern times, Hongmen associations, particularly in Taiwan, have been associated with united front activities.