Social movements are pedagogical spaces for collective learning across difference. Divergent worldviews, interest and identity, historical legacies and relations of power complicate notions of allyship and solidarity for common cause. In this article, we draw on social movement and transformative learning to reflect on our experiences of learning and unlearning as white settler-colonialists researching allyship in the Standing Rock struggle against an oil pipeline in the United States. Our text is also shaped by our own experience as activists within a local Indigenous-led movement to protect ocean and land from the Trudeau-Kinder Morgan oil pipeline. First we introduce ourselves, our research project, context and argument. We then position our work within social movement and transformative learning scholarship, critique notions of allyship and then solidarity. We argue for the unlearning of colonial practices and mindsets which centre our particular white colonial knowledge, leadership, privilege, power and bodies and learning towards decolonising solidarity. To illustrate this process, we present three personal vignettes that speak about the start of our own 'unlearning of ourselves', and learning of decolonising solidarity. We conclude the article with a discussion of how best we believe learning towards decolonising solidarity might proceed in social movements.