How can social participation by older people support their wellbeing? We explore the elder-focused community support system developed in Minamisanriku town after the Great East Japan Earthquake of 2011. Many elderly people lost all their material possessions and were moved from their devastated home communities to temporary housing. We conducted semi-structured interviews with 17 participants including 14 community workers and three members in the Minamisanriku Council of Social Welfare (MCSW) in a programme framed by the MCSW's disaster-response model. Thematic analysis highlighted how older people's involvement in the visiting programme of their temporary community, and conducting twice-daily visits to other vulnerable elders, enabled them to provide valued social support to isolated and homebound peers. It also helped reconstruct their own social identities shattered by the dissolution of former communities, the shock of displacement and loss of possessions. This positive social participation was heavily influenced by strong bridges between their temporary community and MCSW support staff and infrastructure that promoted and supported their visits. Our study highlights how strong and empowering relationships amongst older people can be facilitated by an active government-funded support agency that is immediately responsive to the needs and deeply respectful of the world-views of vulnerable groups.