Peter Hall’s analysis of the Dutch Randstad, in his The World Cities (London: Weidenfeld & Nicolson, 1966), generated the archetype of the polycentric urban region (PUR). Although influential, Hall primarily amplified 1950s’ Dutch planning discourse. This paper analyses the PUR’s genesis, discussing the economic modernization of the 1950s and the preceding decades of crisis and war. By temporalizing Gieryn’s truth-spot theory, the paper constructs a prehistory of the PUR through the biographical trajectories of Dutch geography and planning pioneers Louis van Vuuren, Willem Steigenga, Christiaan van Paassen and Gerrit Jan van den Berg. Planning the PUR is recast as a gentle modernization strategy, signalling new interpretations of polycentricity’s contemporary utility.