Labor history or labour history is a sub-discipline of Social History which specialises on the history of the working classes and the labor movement. The central concerns of labor historians include industrial relations and forms of labor protest (strikes, lock-outs), the rise of mass politics (especially the rise of Socialism) and the social and cultural history of the industrial working classes. Labor historians may also concern themselves with issues of gender, race, ethnicity and other factors besides class but chiefly focus on urban or industrial societies which distinguishes it from Rural history.
Labor history developed in tandem with the growth of a self-conscious working-class political movement in many Western countries in the latter half of the nineteenth century. Whilst early labor historians were drawn to protest movements such as Luddism and Chartism, the focus of labor history was often on institutions: chiefly the labor unions and political parties. Exponents of this institutional approach included Sidney and Beatrice Webb. The work of the Webbs, and other pioneers of the discipline, was marked by optimism about the capacity of the labor movement to effect fundamental social change and a tendency to see its development as a process of steady, inevitable and unstoppable progress. As two contemporary labor historians have noted, early work in the field was "designed to service and celebrate the Labour movement."
In the 1950s to 1970s, labor history was redefined and expanded in focus by a number of historians, amongst whom the most prominent and influential figures were E. P. Thompson and Eric Hobsbawm. The motivation came from current left-wing politics in Britain and the United States and reached red-hot intensity. Kenneth O. Morgan, a more traditional liberal historian, explains the dynamic: