The T.M. Sinclair Packing Company began operating as a slaughtering and processing plant in Cedar Rapids, Iowa in 1870. In 1913 the plant became affiliated with Wilson and Company. In 1935 the plant's name was changed to the Wilson-Sinclair Company. By 1918 the American Meat Cutters and Butcher Workmen of North America began organizing employees. The initial efforts failed in 1921 but were resumed in 1933. Between 1937 and 1939 the local union went on strike at the Wilson-Sinclair Plant, continued to grow its membership, and underwent 2 name changes. In 1937 the local union became part of the CIO and Packinghouse Workers Organizing Committe. In 1939 the local union was granted a charter as United Packinghouse Workers Local Union #3.
From the description of Cedar Rapids CIO organizing in the packinghouse industry : scrapbook, 1937-1939. (Iowa Sate Historical Society). WorldCat record id: 51981980
