The Proto-Norse language developed into Old Norse by the 8th century, and Old Norse began to develop into the modern North Germanic languages in the mid- to late 14th century, ending the language phase known as Old Norse. These dates, however, are not absolute, since written Old Norse is found well into the 15th century.
Old Norse was divided into three dialects: Old West Norse, Old East Norse and Old Gutnish. Old West and East Norse formed a dialect continuum, with no clear geographical boundary between them. For example, Old East Norse traits were found in eastern Norway, although Old Norwegian is classified as Old West Norse, and Old West Norse traits were found in western Sweden. Most speakers spoke Old East Norse in what is present day Denmark and Sweden. Old Gutnish, the more obscure dialectal branch, is sometimes included in the Old East Norse dialect due to geographical associations. It developed its own unique features and shared in changes to both other branches.
The 12th-century Icelandic Gray Goose Laws state that Swedes, Norwegians, Icelanders and Danes spoke the same language, dǫnsk tunga (“Danish tongue”; speakers of Old East Norse would have said dansk tunga). Another term used, used especially commonly with reference to West Norse, was norrœnt mál (“Nordic speech”). Today Old Norse has developed into the modern North Germanic languages Icelandic, Faroese, Norwegian, Danish and Swedish, of which Norwegian, Danish and Swedish retain considerable mutual intelligibility.
In some instances the term Old Norse refers specifically to Old West Norse.
The approximate extent of Old Norse and related languages in the early 10th century:
Relationship to English
Old English and Old Norse were related languages. It is therefore not surprising that many words in Old Norse look familiar to English speakers (e.g., armr (arm), fótr (foot), land (land), fullr (full), hanga (to hang), standa (to stand)). This is because both English and Old Norse stem from a Proto-Germanic mother language. In addition, numerous common, everyday Old Norse words were adopted into the Old English language during the Viking age. A few examples of Old Norse loanwords in modern English are (English/Viking age Old East Norse):
- Nouns – anger (angr), bag (baggi), bait (bæit, bæita, bæiti), band (band), bark (bǫrkʀ, stem bark-), birth (byrðr), dirt (drit), dregs (dræggiaʀ), egg (ægg, related to OE. cognate “æg” which became Middle English “eye”/”eai”), fellow (félagi), gap (gap), husband (húsbóndi), cake (kaka), keel (kiǫlʀ, stem also kial-, kil-), kid (kið), knife (knífʀ), law (lǫg, stem lag-), leg (læggʀ), link (hlænkʀ), loan (lán, related to OE. cognate “læn”, cf. lend), race (rǫs, stem rás-), root (rót, related to OE. cognate “wyrt”, cf. wort), sale (sala), scrap (skrap), seat (sæti), sister (systir, related to OE. cognate “sweostor”), skill (skial/skil), skin (skinn), skirt (skyrta vs. the native English shirt of the same root), sky (ský), slaughter (slátr), snare (snara), steak (stæik), thrift (þrift), tidings (tíðindi), trust (traust), window (vindauga), wing (væ(i)ngʀ)
- Verbs – are (er, displacing OE “sind”) blend (blanda), call (kalla), cast (kasta), clip (klippa), crawl (krafla), cut (possibly from ON kuta), die (døyia), gasp (gæispa), get (geta), give (gifa/gefa, related to OE. cognate “giefan”), glitter (glitra), hit (hitta), lift (lyfta), raise (ræisa), ransack (rannsaka), rid (ryðia), run (rinna, stem rinn-/rann-/runn-, related to OE. cognate “rinnan”), scare (skirra), scrape (skrapa), seem (søma), sprint (sprinta), take (taka), thrive (þrífa(s)), thrust (þrysta), want (vanta)
- Adjectives – flat (flatr), happy (happ), ill (illr), likely (líklígʀ), loose (lauss), low (lágʀ), meek (miúkʀ), odd (odda), rotten (rotinn/rutinn), scant (skamt), sly (sløgʀ), weak (væikʀ), wrong (vrangʀ)
- Adverbs – thwart/athwart (þvert)
- Prepositions – till (til), fro (frá)
- Conjunction – though/tho (þó)
- Interjection – hail (hæill), wassail (ves hæill)
- Personal pronoun – they (þæiʀ), their (þæiʀa), them (þæim) (for which the Anglo-Saxons said híe, hiera, him)
- Prenominal adjectives – same (sami)
In a simple sentence like “They are both weak” the extent of the Old Norse loanwords becomes quite clear (Old East Norse with archaic pronunciation: “Þæiʀ eʀu báðiʀ wæikiʀ” while Old English “híe syndon bégen (þá) wáce”). The words “they” and “weak” are both borrowed from Old Norse, and the word “both” might also be a borrowing, though this is disputed. While the number of loanwords adopted from the Norse was not as numerous as that of Norman French or Latin, their depth and everyday nature make them a substantial and very important part of every day English speech as they are part of the very core of the modern English vocabulary.
Words like “bull” and “Thursday” are more difficult when it comes to their origins. “Bull” may be from either Old English “bula” or Old Norse “buli”, while “Thursday” may be a borrowing, or it could simply be from the Old English “Þunresdæg”, which could have been influenced by the Old Norse cognate. The word “are” is from Old English “earun”/”aron”, which stems back to Proto-Germanic as well as the Old Norse cognates.