Research on folk culture in twentieth-century Britain has focused on elite and transgressive political episodes, but these were not its mainstream manifestations. This article re-evaluates the place of folk culture in twentieth-century Britain in the context of museums. It argues that in the modern heritage landscape folk culture was in an active dialogue with the modern democracy. This story begins with the vexed, and ultimately failed, campaign for a national English folk museum and is traced through the concurrent successes of local, regional, and Celtic 'first wave' folk museums across Britain from the 1920s to the 1960s. The educational activities of these museums are explored as emblematic of a 'conservative modernity', which gave opportunities to women but also restricted their capacity to do intellectual work. By the 1970s, a 'second wave' folk museology is identified, revealing how forms of folk culture successfully accommodated the rapid social change of the later twentieth century, particularly in deindustrializing regions. From this new, museums' perspective, folk culture appears far less marginal to twentieth-century British society. In museums folk culture interacted with mainstream concerns about education, regionalism, and commercialization.