Saxon [Sahsisk in Saxon]
Official Language: Stem duchy of Saxony [only used in the Christian world, endonym is "heritogdôm Sahson", where the words "heritogo" means non-christian king instead of OTL duke]
Language Family: Indo European -> Germanic -> Northsea-Germanic [OTL Northwest Germanic] -> West Germanic [excludes High German dialects which include High Frankish and Langobardic, them forming South Germanic] -> Ingvaeonic -> Saxon
Writing Script: Runic [more accurate a unified modernized Anglo-Frisian one being used in the entire European Heathen world]
Loan words: mostly Saxo-Frisian, Norse [either Western for things from the Atlantic, New World or Africa. While Eastern for things from the Uralic world, East Slavic world or further Islamic-Eurasian world. With dialectal influence from a West Norse dialect in the Dane islands or Denïôiƿa in romanized Saxon], some minor Frankish [OTL word for German dialects inside the North Frankish realm [basically East Francia but with a bit more western territories]] and Latin for Christian things or local interaction (only in South Saxon dialects), Polabian influence in East Saxon dialects and local sects (most loanword are either for the household, place names, animals or for Saxon-Slavic religious sects popular in Obotritia
History: After the liberation of Frisia and the conquest of Frankish border regions after the grand defeat of the Frankish menace. Both Old Frisian and Old Saxon "devolution" back into a mostly unified Ingvaeonic language (except insular English) with Saxon being the dominant force through the century long unification of both tongues with actual Saxon and Frisian acting as dialect groups. After the integration of Jutland (which ATL is mostly Ingvaeonic with Norse influence) and the conquest of Obotritia, came some Polabian and Norse (from the Danish dialect) influence in the dialects of the regions, with Polabian words mostly for wild life, the household or religious Saxon-Slavic sects in Obotritia. During the Norse high age came a bunch of Norse loanwords and more influence in the coastal cities and Jutland. Words describing things in the New World, Andalus and Africa mainly coming through Væstríki while information and words from the Islamic, East Slavic, Uralic and Eurasian world coming through Gautrike. Frankish loanwords are few outside of border dialects through limited trade. Latin loanwords almost don't exist outside of Pre-Saxon loanwords. If anything Latin/Frankish loanwords are only for Christian things, like Christ, Churche for Abrahamic house of worship etc. Also native words changed meaning, like kuniŋ and kuniŋdôm is only used in the sense of Abrahamic rulers/realms, god is only used in the sense of the Abrahamic god, other gods regardless of non-Abrahamic religions are called ôs, plural ôse. If we compare it with ATL English, then you can imagine Saxo-Frisian being a mix of OTL Icelandic and North Korean... Korean, less loanwords, more linguistic purism and more archaic features. Also thanks to Pagan Saxony not having such bad relations with the Jews like the Christians, there was a major exodus from Jews and Roma from Christian lands to þjœtic (Germanic paganism) Saxony where the Roma could worship their ôse and Jews work without restrictions, thus we have minor Judeo-Saxon and Romani influence in some bigger cities, as well as a few Saxons worshipping Vedic ôse like Kali.
Heres's a rough map of Saxony and it's languages. The dots represent a minority language/dialect in the region;
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