In Old English, we see the word 'êac' listed as an adverb with the
meaning 'also'. Old English 'êa' is almost always equivalent to Old
Norse 'au'. Given that Old English and Old Norse both derive from
what many are calling North West Germanic, we would have to conclude
that 'auk' is the elder brother. However, their are several problems
with this position: 1) 'o' from 'au' makes phonological nonsense and
is without precedent in Old Norse phonology 2) Old English 'auk' is
listed as an adverb rather than as a conjunction 3) both the brothers
'ok' and 'auk' can be found somewhere in every dialect of Old Norse
from about 800-1250. If we look to Gotlandic, which otherwise shows
many archaic features not found in other dialects, we see both 'auk'
and 'ok' on everything from Viking Age runestones to manuscripts of
the 13th century. Both brothers also make regular appearances on Old
Danish and Swedish runestones. In the West Norse domains of western
Norway, Iceland and the Faroes, we see that brother 'ok' is clearly
in charge by the end of the Viking Age. Nevertheless, 'auk' appears
as late as the 13th century in West Norse domains. As Moltke pointed
out, the early Viking Age spelling 'åuk' clearly points to the pro-
nounciation 'ok', which would also seem clear from manuscripts of
West Norse where 'ok' is almost universal. Nevertheless, 'auk' does
occur in West Norse. The late 12th or early 13th century Gotlandic
writer of the Guta Lagh (laws of the Goths) shows no preference for
either brother, writing both 'auk' and 'ok' regularly. Nowhere else
in Old Norse do we see this strange parallelism of 'au' and 'o'. In
fact, the more we examine the brothers 'auk' and 'ok', the stranger
they seem. Did they really have the same parent? Is one of them an
adopted brother? We know that early Indo-European languages used an
enclitic form of 'and', usually appearing at the end of a compound.
It is, therefore, possible that the brothers 'auk' and 'ok' each had
a separate parent: 1) as an enclitic 2) as a free conjuction proper.
Unfortunately, the brothers' East Gothic cousin 'jah' has little or
nothing to say about his cousins' parentage, and Old English cousin
'and' seems positively unrelated. ok/auk/êak/and/jah more from the
phonological funnies later. Your contributions to the phonological
funny pages are welcome.

Regards,
Konrad.