alternatehistory.com

Sorry for the late reply!

It is a bit complicated but the short version is, that "Araldyana" more or less translates as "Land of the kin of Harald"

Here is the long version:

IOTL we would write it as "Haraldiana". As a result of growing political and cultural influence of the *Norse in Britain during the medieval period, the Romano-British culture adopted some of the newcomers practices. Regarding "Araldyana" especially the revival of patronymics is important.

Around the turn of the millennium the Romano-British and the Norse-British ruling classes had effectively merged, but due to the legacy and prestige of the Empire, Latin remained the unchallenged language of government and indeed efforts to "purify" court Latin were quite influential during this time.

This led to the (re-)introduction of some (perceived) ancient practices, such as the suffix "-ianus" to denote of offspring. The official main source of inspiration for this was of course Augustus aka Octavianus, but it was actually more influenced by an eclectic sense of aesthetic, than by the actual practices of their Roman forefathers.

With OTL ortogrphy this would look something like this:

*Haraldsson = Haraldianus
*Haralding ("kinsman of Harald") = Haraldianus

But what about the difference in spelling?

In TTL version of medieval Latin, more specifically British Court Latin, the letter "y" was originally used as a spelling variation of "i" but has been increasingly used to denote the sound /j/ after the letters "g", "d", "c" and "t".

ITTL a small group of native (Vulgar) Latin speakers survive on the British Islands but they were heavily influenced by continental Romance (mostly TTL *French), leading to "dia" being pronounced as /d͡ʒa/. This pronunciation is mostly considered to be a butchered version of the more classical /dja/.