Recent work in environmental psychology and education emphasizes environmental identity as important in predicting a broad array of environmental behaviors. However, there are gaps in understanding how other social identities interact with environmental identity. We conducted semi-structured interviews with 30 undergraduate students from diverse backgrounds supplemented by environmental identity and demographic surveys. Our interviews showed that gender and race/ethnicity affect the development of undergraduate environmental identity by influencing (1) significant life experiences (SLEs) with nature and (2) important social influences in environmental identity development. In particular, gender and race impacted relationships with mentors, gender stereotypes limited potential SLEs, and gendered physical concerns constrained environmental activities. Other themes included the role of socio-economic status and nature as a source of empowerment. Our work suggests that research is needed on the interplay among different identities and environmental identity, and that further work is necessary to make the environmental field inclusive for all.