Mathematical identity is considered as the multi-faceted relationship that an individual has with mathematics, including knowledge and experiences, perceptions of oneself and others. The SCoTENS funded project, named MIST, examined the mathematical identity of student teachers who had chosen to specialise in mathematics in their B.Ed. programme. Students were drawn from two institutions, one in Northern Ireland, one in the Republic and narrative was used as a tool to access mathematical identity. This paper reports on the analysis of similarities and differences between the mathematical identity of these students teachers in each part of the island of Ireland and discusses how this informs our reflections on the mathematical education experienced.