Early career teachers (ECTs) are situated in a dynamic contextual landscape that both influences their development and practice and dictates professional expectations for instruction and professional learning. This systematic review of international research literature sought to establish the understanding of teacher induction and mentoring program support of ECTs through the following research questions: 1) which nations and regions are represented in research literature that details formal or programmatic support of ECTs? 2) what international research evidence is there to describe various contextual factors that affect experiences of ECTs? and, 3) how do teacher induction and mentorship programs respond to the various contextual factors affecting ECTs? Upon detailing our review method and sampling procedures, we synthesize the convergences and divergences of the findings within each of the contextual factors. The conceptualization of contextual factors in this review included social, political, cultural, organizational, and personal forces that influence the professional practices of ECTs. Finally, we summarize the review findings in a heuristic model that offers a visual representation of the implications of our findings, and discuss the implications for policy, practice, and future research.