This study examined the presence of identity in diverse online courses and explored how presence of identity correlated with content and students' participation in online discussion and hence knowledge building in online educational spaces. Epistemic and participation data regarding online interaction and knowledge building were collected from a diverse group of students enrolled in seven multi-disciplinary online courses. Both qualitative and quantitative findings of the study suggested that online discussions with identity presence were associated with more follow-up participation and reinforced a more dialogic online interaction. Identity presence was also correlated with online interactions of knowledge sharing and egocentric elaboration.