A US industrial trade union, founded in 1869 at a tailors’ meeting in Philadelphia. By 1879 it was organized on a national basis, with membership open to all workers. Its goals were reformist rather than radical, and included the demand for an eight-hour day. Its growth was phenomenal. In 1882 the Knights helped push through Congress the Chinese Exclusion Act, prohibiting the entry into the USA of Chinese labourers. The union was at its height in 1886 under the leadership of Terence V. Powderly, with a membership of almost a million, but declined thereafter, partly due to involvement in unsuccessful strikes and to general antipathy to labour organizations after the Haymarket Square riot. Factional disputes reduced its membership after the American Federation of Labor was founded, and by 1900 it was virtually extinct.