The paper provides an overview of the mutual migrations of Slovenians in Bosnia and Herzegovina and the Bosnian-Herzegovinian ethnicities to Slovenia, with an emphasis on their history in the 20th century, when the state framework was first the common Habsburg Monarchy, then the Kingdom of Yugoslavia, and finally, for the longest period, socialist Yugoslavia. The contribution pays special attention to the historical turning point represented by the disintegration of the Social Federal Republic of Yugoslavia, starting with the political departure from the federal state and the proclaimed independence of the Republic of Slovenia and the Republic of Croatia. After the successful military defence of the independent Slovenian state against the Yugoslav People’s Army during the short-lived Slovenian Independence War in 1991, the international recognition of the two republics as new independent European states followed very quickly. Somewhat unsurprisingly, in 1992, a disintegration characterised by several years of bloodshed between the ethnicities began in the rest of Yugoslavia. As a multi- -ethnic state community, Yugoslavia had been created peacefully, but it fell apart violently due to ethnic reasons. The final part of the paper discusses the social circumstances of the collapse of the common state and its direct consequences for the Yugoslav nations in Slovenia and Bosnia and Herzegovina. The author focuses on the ethical issues of the Yugoslav state’s dissolution.