History of the Diæresis

Rather than leaping into a search for the best way to keyboard Coptic, I have decided to step back and examine each of the three necessary diacritics in the Coptic alphabet first. These three are the diaeresis, the overline denoting a nomina sacra or abbreviation, and the jinkim which looks like a macron and gives the consonant a syllabic quality. There are other diacritics but these three occur most often in the manuscripts and have such a diverse and obscure history that I think I will start here and not worry about the others for now.

The papyri in this image, P52, represents the earliest dated instance of the diaresis that I have been able to find. This fragment is a portion of the crucifixion story and is dated 125 - 150 CE.

In this case the diaeresis is at the beginning of a word. In the second line the text reads 'oudena ina' and the diaeresis serves to indicate that the 'i' is pronounced separately from the 'a'. It actually begins a new word and new clause. There also appears to be a trace of a diaereis on the third letter of the top line.

This is the only discussion of the early history of the diaresis that I have found.

[U]ndoubtedly the occurrence of diaeresis and the omission of iota adscript can be used as criteria of date and, comparatively rare at the beginning of the second century, were increasing in frequency with each successive decade. Statistics for these phenomena do not appear to have been collected (a systematic investigation of the subject might be of some value for palaeography), but such search as it has been possible to make shows that the date assigned to 1 is not affected by them.

The use of diaeresis over i or u was exceedingly rare till the second century, but it was not entirely unknown before then. Originally introduced to distinguish as separately pronounced a vowel accompanying another vowel with which it would otherwise make a diphthong, the usage was soon extended to vowels standing alone, and therefore became meaningless.

It is only the latter use which is relevant to the present case. P. Fay. 110 (A.D. 94) contains in euu`perbaton (l. 9) and twi i`diwi (l. 2) instances of diaeresis which, though an extension of the original use, cannot be regarded as wholly incorrect, since adjoining vowels are being distinguished; but i`na (ibid., 11.6, 9) is a clear case of the incorrect use, dusi u`dasi (l. 17) is at best a further extension of the use in euu`perbaton and twi i`diwi.

Systematic search might perhaps reveal other early examples, but so far as the statistics collected are concerned there are none in exactly dated documents before A.D. 110. (From Fragments of an Unknown Gospel )

The article goes on to discuss the 'correct' versus the 'incorrect' way to use the diaeresis, which seems like a tedious approach to me. I am relieved to find in antiquity the occasional lack of respect for rigid spelling standards.

I have also scanned through pages of prechristian papyri without finding the shadow of a diaeresis. I would love to hear more about this history and earlier diaereses if they exist.

Update: I misspelled diaeresis in the title and almost left it but 'diaresis' doesn't google as well as
'dieresis' or 'diaeresis.'