Frankish (reconstructed Frankish: *Frankisk), also known as Old Franconian or Old Frankish, was the West Germanic language spoken by the Franks between the 4th and 8th century.

Between the 5th and 9th centuries, Frankish spoken by the Salian Franks in Belgium and the Netherlands evolved into Old Dutch (Old Low Franconian).

After the Salian Franks settled in Roman Gaul, its speakers in Picardy and Île-de-France were outnumbered by the local populace who spoke Proto-Romance dialects, e.g. Old French. However, a number of modern French words and place names, including the country name "France", have a Frankish (i.e. Germanic) origin. France itself is still known by terms meaning the "Frankish Realm" in languages such as German (Frankreich), Dutch (Frankrijk), the derived Afrikaans (Frankryk), and Danish (Frankrig).

The Old Frankish language is poorly attested and mostly reconstructed from Frankish loanwords in Old French, and from Old Dutch, as recorded in the 6th to 12th centuries. A notable exception is the Bergakker inscription, which may represent a primary record of 5th-century Frankish.

Nomenclature

Germanic philology and German studies have their origins in the first half of the 19th century when Romanticism and Romantic thought heavily influenced the lexicon of the linguists and philologists of the time, including pivotal figures such as the Brothers Grimm. As a result, many contemporary linguists tried to incorporate their findings in an already existing historical framework of "stem duchies" and Altstämme (lit. "old tribes", i.e. the six Germanic tribes then thought to have formed the "German nation" in the traditional German nationalism of the elites) resulting in a taxonomy which spoke of "Bavarian", "Saxon", "Frisian", "Thuringian", "Swabian" and "Frankish" dialects. While this nomenclature became generally accepted in traditional Germanic philology, it has also been described as "inherently inaccurate" as these ancient ethnic boundaries (as understood in the 19th century) bore little or limited resemblance to the actual or historical linguistic situation of the Germanic languages. Among other problems, this traditional classification of the continental West Germanic dialects can suggest stronger ties between dialects than is linguistically warranted. The Franconian group is a well known example of this, with East Franconian being much more closely related to Bavarian dialects than it is to Dutch, which is traditionally placed in the Low Franconian sub-grouping and with which it was thought to have had a common, tribal origin.

In a modern linguistic context, the language of the early Franks is variously called "Old Frankish" or "Old Franconian" and refers to the language of the Franks prior to the advent of the High German consonant shift, which took place between 600 and 700 CE. After this consonant shift the Frankish dialect diverges, with the dialects which would become modern Dutch not undergoing the consonantal shift, while all others did so to varying degrees. As a result, the distinction between Old Dutch and Old Frankish is largely negligible, with Old Dutch (also called Old Low Franconian) being the term used to differentiate between the affected and non-affected variants following the aforementioned Second Germanic consonant shift.