largest Baptist group in the British Isles, organized in 1891 as a union of the Particular Baptist and New Connection General Baptist associations. These groups were historically related to the first English Baptists, who originated in the 17th century.

The Baptist Union is a voluntary organization made up of area associations of churches, individual churches, colleges, and individual members. In the 20th century it has become more centrally organized. Its activities include education, ecumenical relations, missions, and social welfare, but it cannot interfere in the autonomy of the local churches. Headquarters are in London.