Old Swedish

Old Swedish (Modern Swedish: fornsvenska) is the name for two distinct stages of the Swedish language that were spoken in the Middle Ages: Early Old Swedish (Klassisk fornsvenska), spoken from about 1225 until about 1375, and Late Old Swedish (Yngre fornsvenska), spoken from about 1375 until about 1526.

Old Swedish developed from Old East Norse, the eastern dialect of Old Norse. The earliest forms of the Swedish and Danish languages, spoken between the years 800 and 1100, were dialects of Old East Norse and are referred to as Runic Swedish and Runic Danish because at the time all texts were written in the runic alphabet. The differences were only minute, however, and the dialects truly began to diverge around the 12th century, becoming Old Swedish and Old Danish in the 13th century. It is not known when exactly Elfdalian began to diverge from Swedish.

Early Old Swedish was markedly different from modern Swedish in that it had a more complex case structure and had not yet experienced a reduction of the gender system and thus had three genders. Nouns, adjectives, pronouns and certain numerals were inflected in four cases: nominative, genitive, dative and accusative.