The National Brotherhood of Operative Potters was a labor union formed in 1890 in East Liverpool, Ohio. The pottery workers who formed the union broke away from their prior involvement with the Knights of Labor because they felt unionists from Trenton, N.J. were too dominant in the organization.
By the early 20th century, the NBOP had approximately 6,500 members, most in Ohio and some in West Virginia. They negotiated a uniform wage contract with management of the pottery manufacturers in those states. After strikes in the early 1920s, union membership began to decline. After the Depression, as working conditions improved, the union's membership grew to over 19,000. The group changed its name to the International Brotherhood of Operative Potters in 1951 and to the International Brotherhood of Pottery and Allied Workers in 1969.