BACKGROUND: Many people refuse vaccination and it is important to understand why. Here we explore the experiences of individuals from Gypsy, Roma, and Traveller groups in England to understand how and why they decided to take up or to avoid COVID-19 vaccinations. METHODS: We used a participatory, qualitative design, including wide consultations, in-depth interviews with 45 individuals from Gypsy, Roma, and Traveller, communities (32 female, 13 male), dialogue sessions, and observations, in five locations across England between October 2021 and February 2022. FINDINGS: Vaccination decisions overall were affected by distrust of health services and government, which stemmed from prior discrimination and barriers to healthcare which persisted or worsened during the pandemic. We found the situation was not adequately characterised by the standard concept of "vaccine hesitancy". Most participants had received at least one COVID-19 vaccine dose, usually motivated by concerns for their own and others' health. However, many participants felt coerced into vaccination by medical professionals, employers, and government messaging. Some worried about vaccine safety, for example possible impacts on fertility. Their concerns were inadequately addressed or even dismissed by healthcare staff. INTERPRETATION: A standard "vaccine hesitancy" model is of limited use in understanding vaccine uptake in these populations, where authorities and health services have been experienced as untrustworthy in the past (with little improvement during the pandemic). Providing more information may improve vaccine uptake somewhat; however, improved trustworthiness of health services for GRT communities is essential to increase vaccine coverage. FUNDING: This paper reports on independent research commissioned and funded by the National Institute for Health Research (NIHR) Policy Research Programme. The views expressed in this publication are those of the authors and not necessarily those of the NHS, the NIHR, the Department of Health and Social Care or its arm's length bodies, and other Government Departments.