Many natural resources have degraded and collapsed despite being managed under rigorous institutional frameworks set up to ensure rational exploitation. Path dependency of dysfunction institutions has been suggested as an explanation for such undesired outcomes. We explore the role of path dependency in natural resource management by studying a 100-year evolution of Swedish fisheries. We rely on three main types of original longitudinal data collected for the period 1914–2016: (A) policy documents, (B) government spending on management and subsidies, and (C) catch and fleet data. Our analysis contrasts the periods before and after the Swedish entrance into the European Union (1995) because this marks the year when fisheries policy became beyond the direct influence of the Swedish government. We uncover four pieces of evidence suggesting the existence of a path dependent dynamic in the pre-EU period: (1) despite increasing insights on the vulnerability of fish stocks to overexploitation, national policy goals in relation to fisheries continuously promoted incompatible goals of social and economic growth but without any reference to the sustainability of the biological resources; (2) the same policy instruments were used over long periods; (3) actor constellations within the fisheries policy subsystem were stable over time; (4) neither political regime nor macroeconomic variables and fisheries performance (industry production, oil price, landing values) could explain observed temporal variation in subsidies. We conclude that key policy actors in the pre-EU period formed an “iron triangle” and thereby prevented necessary policy changes. These national reinforcing feedbacks have been weakened since EU entrance, and the indicators for path dependency show broader involvement of stakeholders, a shift in spending, and policy goals that now explicitly address ecological sustainability.