Abstract: The aim of this article is to discuss the Yiddish varieties of Courland and Estonia in the general context of the co-territorial languages: Baltic German, Latvian, Livonian, and Estonian. As a rule, discussion of Yiddish in the region is mostly based on the classical descriptions of the Yiddish varieties from the beginning of the 20th century. It is demonstrated that common features in phonology and lexicon of Courland (and Estonian) Yiddish and Baltic German are, in fact, regional and attested at least in varieties of Estonian but often in Latvian and Livonian as well. It is argued that due to the multilingualism of Jews in the region, a wider perspective of modern contact linguistics and multilingualism and analysis is needed. In the 20th century, multilingual speech was a norm at least among Estonian Jews, and, based on fieldwork data from the 1990s among multilingual Estonian Jews, there is no clear preference of insertional or alternational code-switching. However, if alternational code-switching is preferred in a community, it might explain the low number of conventionalised lexical borrowings (as is the case for Latvian borrowings in Yiddish).
