Proto-Basque

Proto-Basque (Basque: Aitzineuskara; Spanish: protoeuskera or protovasco; French: proto-basque) is a reconstructed predecessor of the Basque language, before the Roman conquests in the Western Pyrenees.

The first linguist to scientifically approach the question of the historical changes that the Basque language had undergone over the centuries was Koldo Mitxelena. His work on Proto-Basque focused mainly on the period between the 5th century BCE and the 1st century CE, the period just before and after initial contact with the Romans.

The main method he employed was that of internal reconstruction as Basque has no known genetic relatives, rendering comparative methods unworkable. By comparing variants of the same word in the modern dialects and the changes Latin loanwords had undergone, ancestral forms and the rules for historical sound changes were deduced.

Koldo Mitxelena's groundbreaking work, which culminated with the publication of his book Fonética histórica vasca (1961) was mostly carried out before the Aquitanian inscriptions were found, which fully backed up Mitxelena's proposed Proto-Basque forms.

Since then, a number of other prominent linguists such as Larry Trask, Alfonso Irigoien, Henri Gavel and most recently Joseba Lakarra, Joaquín Gorrotxategi and Ricardo Gómez have made further contributions to the field. Some of them, such as Lakarra, have focused their attention on even older layers of the language (Pre-Proto-Basque) preceding the Celtic invasion of Iberia.

Studying the behaviour of Latin and early Romance loanwords in Basque, Koldo Mitxelena discovered that proto-Basque *n became lost between vowels, and similarly that proto-Basque had no *m. Both are relatively unusual changes cross-linguistically, although /n/ was also deleted between vowels in the history of the nearby Portuguese language.

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