The First Grammatical Treatise (Icelandic: Fyrsta málfræðiritgerðin ['f?(r?)sta 'mau:l?frai:ðr?:t?c?rð?n]) is a 12th-century work on the phonology of the Old Norse or Old Icelandic language. It was given this name because it is the first of four grammatical works bound in the Icelandic manuscript Codex Wormianus. The anonymous author is today often referred to as the "First Grammarian".
This work is one of the earliest written works in Icelandic (and in any North Germanic language). It is a linguistic work dealing with Old Norse, in the tradition of Latin and Greek grammatical treatises, generally dated to the mid-12th century. Hreinn Benediktsson was not able to narrow the time of writing more precisely than to 1125-1175.
The First Grammatical Treatise is of great interest to the history of linguistics, since it systematically used the technique of minimal pairs to establish the inventory of distinctive sounds or phonemes in the Icelandic language, in a manner reminiscent of the methods of structural linguistics. It is also notable for revealing the existence of a whole series of nasal vowel phonemes, whose presence in the Icelandic language of the time would otherwise be unknown.
The Treatise is important for the study of Old Norse, as it is a major text showing the state of the language just prior to the writing of the Icelandic Sagas. It also provides a comprehensive study of the pronunciation of the language, to the extent that it created an Icelandic alphabet derived from the Latin, and more adapted to writing on paper or parchment than the older, epigraphic Runic alphabet that was made for shorter carvings on wood or stone. (Other writings in the Latin alphabet presumably existed in the form of law books and Christian writings. The educated clergy of the time would not have used runes.) This alphabet included þ (derived straight from the runes), as well as diacritic indication of vowel length, and an o with an ogonek. The First Grammarian's entire system was never adopted, as evidenced in later manuscripts, in some cases not much younger, but it has had an influence on Icelandic writing ever since (see above). See Icelandic orthography.
Raddarstafir (Vowels): a, ?, ?, , e, ?, ?, , ?, i, o, ?, ø, ø?, u, u?, y, ?
Samhljóðendr (Consonants): b, ?, c, ?, d, ?, f, ?, g, ?, ?, h, l, ?, m, ?, n, ?, p, ?, r, ?, s, ?, t, ?, þ
Samsettar (Letters for composite sounds): x, z
Other: ?, ~
The author is unknown, and is usually referred to as "First Grammarian". Scholars have hypothesized various identities for the First Grammarian. One probable candidate is Hallr Teitsson (born ca. 1085, died 1150). Þóroddr Gamlason has also been suggested.