This International Mine Mill & Smelter Workers membership book belonged to Giovanni Ardissone. The Stamp inside indicates he belonged to Butte local No. 1. Butte, Montana was one of the major battlegrounds of Mine Mills predecessors the Western Federation of Miners and the Industrial Workers of the World. Dues Stamps inside span the years 1940-1943. Mine Mill was one of 11 unions purged from the C.I.O. for refusing to expel their radicals from leadership after the passage of Taft-Hartley in 1947. Mine Mill was one of the more militant and radical of the CIO unions and as such faced harsh repression from employers and the U.S. & Canadian governments. After the purges, Mine Mill survived independently until 1967. The United Steelworkers raided and picked off their jurisdiction one by one until the eventual merger of Mine Mill into USW was negotiated on the terms that Mine Mill leaders would remain in leadership in the ne wly merged union.