History of Danish

The Danish language developed during the Middle Ages out of the Old East Norse, the common predecessor of Danish and Swedish. It was a late form of common Old Norse. The history of Danish can by convention be divided into:

Old East Norse is in Sweden called Runic Swedish and in Denmark Runic Danish, but until the 12th century, the dialect was the same in the two countries. The dialects are called runic because the main body of text appears in the runic alphabet. Unlike Proto-Norse, which was written with the Elder Futhark alphabet, Old Norse was written with the Younger Futhark alphabet, which only had 16 letters. Due to the limited number of runes, some runes were used for a range of phonemes, such as the rune for the vowel u which was also used for the vowels o, ø and y, and the rune for i which was also used for e.

A change that separated Old East Norse (Runic Swedish/Danish) from Old West Norse was the change of the diphthong æi (Old West Norse ei) to the monophthong e, as in stæin to sten. This is reflected in runic inscriptions where the older read stain and the later stin. There was also a change of au as in dauðr into ø as in døðr. This change is shown in runic inscriptions as a change from tauþr into tuþr. Moreover, the øy (Old West Norse ey) diphthong changed into ø as well, as in the Old Norse word for "island".

Fangær man saar i hor seng mæth annæns mansz kunæ. oc kumær han burt liuænd....
"If one catches someone in the whore-bed with another man's wife and he comes away alive..."

takær bondæ annær man mæth sin kunæ oc kumar swa at han dræpær anti mannen....
"If a peasant takes another man with his wife and does it happen that he does not kill the man..."

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Wikipedia