This paper draws upon a longitudinal study on beginning teachers and their experiences of becoming and being a teacher in unprecedented challenging circumstances in Portugal. It focuses on the ways in which changes in policy and school context and in their personal and professional context, impact upon teachers’ professional identity. These will be analyzed drawing upon the stories of two beginning teachers. Their accounts will be used to illustrate the key influencing factors that have impacted upon the development of their professional identities. Four main themes emerged from the data: the influence of context, both at a policy and social level and at a school level; the importance of relationships in teaching, particularly with students and colleagues; the emergence of inner tensions resulting from the mismatch between strong beliefs and reality; and the role of emotions in (re)defining teachers’ practice of teaching and teachers’ identity development. Teaching is very demanding and teachers do experience a wide range of positive and negative emotions, especially when social recognition, trust, respect and professional practice are challenged. The paper concludes with the discussion of the findings and their implications, namely the importance of changing contexts of teaching in defining, justifying and transforming teachers’ identities.