In the 1910s and 1920s, Black musicians organized more than fifty independent locals within the American Federation of Musicians (AFM) in an attempt to control audition criteria, set competitive wages, and secure a voice in national decision-making. Leta Miller follows the AFM's history of Black locals, which competed directly with white locals in the same territories, from their origins and successes in the 1920s through Depression-era crises to the fraught process of dismantling segregated AFM organizations in the 1960s and 70s. Like any union, Black AFM locals sought to ensure employment and competitive wages for members with always-evolving solutions to problems. Miller's account of these efforts includes the voices of the musicians themselves and interviews with former union members who took part in the difficult integration of Black and white locals. She also analyzes the fundamental question of how musicians benefitted from membership in a labor organization.

Broad in scope and rich in detail, Union Divided illuminates the complex working world of unionized Black musicians and the AFM's journey to racial inclusion.