The theory of Abkhaz migrated to Abkhazia in late middle ages appeared in Georgian academic circles in the Stalinist period (see Pavle Ingorokva, has been discredited and revived again after Glasnost. See for example Under Siege: Inter-Ethnic Relations in Abkhazia by Tom Trier et al: "More radical Georgian historians posit that those who today identify as Abkhazians are in fact migrants from the North Caucasus...". Bruno Coppieters echoes this in Europeanization and conflict resolution: case studies from the European periphery, p. 196  "But a radical ... section of the Georgian national movement saw Abkhaz ... not as an autochthonous community of Abkhazia".  

 Actually there's a lot of radical (pseudo-)historical literature from both sides of the conflict, so we tried to use mostly Western sources. Let's think about whether these theories deserve to be mentioned (and where) and how to put them in proper context. If we just list all the claims by radicals from both sides we'll have to split the article into two separate narratives.