Political sociology studies the social foundations of political authority, treating political life as shaped by social structure, cultural values and economic arrangement instead of explicable in its own terms.
Max Weber is its founding figure in the modern form. His typology of legitimate authority as traditional, charismatic and legal-rational, and his analysis of bureaucracy as the characteristic form of modern domination, gave the field its core vocabulary. His definition of the state by its monopoly of legitimate violence, and not by its purposes, remains the standard starting point. Marx stands behind the field as a forerunner. The Italian elite theorists supplied its most uncomfortable finding: Mosca, Pareto and Michels, whose iron law of oligarchy held that organization as such tends to produce rule by the few, including inside organizations founded to prevent it.
The postwar field turned to large comparative questions. Lipset examined the social requisites of democracy. Barrington Moore's Social Origins of Dictatorship and Democracy (1966) traced divergent political outcomes to the class coalitions formed during commercialization. Skocpol's States and Social Revolutions (1979) argued that revolutions are made by state breakdown and not by revolutionaries. Tilly turned the causal arrow around, showing how war-making built the European state.
The persistent objection is methodological. Structural explanation leaves too little room for contingency, leadership and ideas; it can account for why a regime is vulnerable but not for why it falls in the particular week it does. The field has absorbed that criticism more than it has answered it, and its current work on democratic backsliding and cleavage realignment is noticeably more attentive to political agency than the structuralist generation was.