[4] In the second half of the second century there were major changes in the composition of the population, but the organic continuity of the Latin language development of the area is unbroken.

[5] The particularly destructive Marcomannic Wars changed the ethno-linguistic makeup of the province: speakers of the indigenous Celtic and Illyrian languages decreased in number, to be replaced by immigrants of different culture.

Almost all families fled by the establishment of the Avar Khaganate in the second half of the 6th century, many moving to the Croatian coast or being taken by the Lombards into the Italian Peninsula.

[7][8] Analysis of the Vulgar Latin spoken in Pannonia showed several phonetical developments:[5][9] As in other provinces, accusatives after the 1st century AD were regularly switched to nominatives as the subjects of verbs, ergo -as was often written instead of -ae, which is the correct plural inflection of first-declension feminine nouns.

[12] An examination of the Pannonian Latin texts as a whole reveals that the process of amalgamation has only begun in linguistic singular.