Here is what one German user wrote on Historum about the Great Wilderness (before Lithuania Minor):
http://hostarea.de/show.php/334189_ragnit04.45.jpg.html
Sorry I can't make this link work...
The definite evidence of the existence of Old Prussians (and Lithuanians) would be tax registers. These tax registers prove that the territory of what became Prussian-Lithuania later was uninhabited round 1400 - except for some bee-collectors, hunters etc., and the settlements islands I mentioned."
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This user also claimed there is no linguistic evidence that Lietuvninkai dialect was influenced by Old Prussian.
Quote:
"There is also a strong linguistic argument:
If Old Prussians and Lithuanians had lived together in villages situated in this territory before the date of arrival of Lithuanians accepted by historians (that is, after the Treaty of Melno in 1422), then the Old Prussian language would have impacted the Prussian-Lithuanian language that is documented in the 16th century. The fact is: we find no Old Prussian substrat or adstrat, instead this Prussian-Lithuanian language abounds in Slavisms: ruthenisms and polonisms wherever you look.
A few examples:
sermon: KOZONIS (Polish KAZANIE)
pulpit: KOZELNYCZIA (Polish KAZALNICA)
building: BUDAWONE (Polish BUDOWA)
(biblical)/ship: AKRUTAS (Polish OKRET)
order(-liness): DAWADAS (Polish DOWOD)
pious: NOBAZNAS (Polish NABOZNY)
prophet: PARAKAS (Polish PROROK)
free: WALNAS (Polish WOLNY) Freiheit/liberty: WALNYBE
army: WAISKAS (Polish: WOJSKO)
WEEKDAYS.
1. panedelis <- понедельник [panedelnik] <- по (before) + неделя (week)
2. utarnikas <- вторник [vtornik] <- второй (second)
3. sereda <- Belarusian cяpэдa [syareda]
4. ketwergas with k- instead of č- seems non Slavic, but in Russian четверг [četverg]
5. petnyčia <- пятница [pyatnitsa/petnica] <- пять (five)
6. subata <- суббота [subota]
7. nedelia <- неделя [nedelya] (week)"