This article presents empirical evidence from two contemporary diasporas to support the thesis that formal return to the homeland does not necessarily “unmake” diasporas, as some scholars have previously suggested. I argue that, instead, so-called reverse diaspora formation processes take place, with important repercussions for the acculturation of co-ethnic immigrants in their nominal “homelands.” This article focuses on this latter issue, primarily on processes of identity formation and notions of belonging and home, which are particularly meaningful in the context of this diasporic “homecoming.” It draws on the structured comparison of the ethnic Greek and ethnic German diasporas from the former Soviet Union who moved to Greece and Germany after perestroika. Despite their rich and illuminating analogies and overlaps, these two diaspora groups have never been compared and contrasted before. After a brief historical contextualization, complicated processes of identity negotiation and belonging in the putative “historical homelands” are investigated comparatively, lending credence to the idea that “reverse” German and Greek diasporas have developed within (and often in conflict with) contemporary Greek and German societies. The fact that they occur simultaneously in both countries tends to suggest that the concept of reverse diaspora is an important one that needs closer attention from scholars in the future. The article concludes by outlining how we may conceptualize a reverse diaspora, based on existing definitions of diaspora. My research materials consist of in-depth qualitative data collected over the course of six years by means of eighty-one semi-structured interviews in Russian, German, and Greek with migrants and experts in Greece and Germany, embedded in ethno-graphic research and supplemented by statistical data.