Romanian Slavonic was the official written language in the principalities of Moldavia & Wallachia from the very beginning of these countries until early 17th century (& shared by Transylvanians).
It clearly originated in Medio(Middle) Bulgarian but had peculiarities of its own.
It clearly originated in Medio(Middle) Bulgarian but had peculiarities of its own.
Serbian influence was notable from the beginning in Wallachia & after 1510s started to be seen in Moldavian documents as well. It is about using Serbian forms of different words or expressions.
There was also Ruthenian & Polish influence seen in Moldavia from start.
There was also Ruthenian & Polish influence seen in Moldavia from start.
Also, from the earliest documents one can see in many cases (& variable from document to docmnt) Romanian influence. This goes from words & names, sintax, suffixes, declinations of Slavic words per Romanian rules. It is obvious in many cases the writers were Romanian speakers.
There have been counted in the Romanian-Slavonic documents before 1500 more than 1700 Romanian words of mostly nonSlavic origin or with forms present only in Romanian.
Romanian does have several 10s of Slavic origin words not extant in those forms in modern Slavic languages.
Romanian does have several 10s of Slavic origin words not extant in those forms in modern Slavic languages.
Also notable that administrative & business docmnts were much more permissive to "inovations" than the religious ones, but the latter were not immune either.
Romanian was introduced gradually from 1520s, again 1st in non-religious texts but in 1540s we have Holy texts in Ro..
Romanian was introduced gradually from 1520s, again 1st in non-religious texts but in 1540s we have Holy texts in Ro..
Inflexion point was noted during the Matei Basarab reign (1632-1654) when Romanian use > Slavonic one (65/35%) & Ro reaches about 40% for religious texts as well.
there is a nice PhD thesis on this subject.
there is a nice PhD thesis on this subject.

On religious side the conservatism was deeper. Romanian was initially allowed just fro sermons not for liturgy. The higher clergy stressed repeatedly that Orthodoxy was meant to be conveyed only in Greek & Slavonic.
As affect we had a Slavicisation of Romanian religious slang notable to nowadays notable in preference for Slavic words when alternatives are available & for Slavic language suffixes, not otherwise in use.
Basically Latin sounding stuff was considered heretical...
Basically Latin sounding stuff was considered heretical...

Notable exception was religious music where Greek had pre-eminence since 1400s (>80% of written songs preserved were in Greek even during Stephen the Great's reign).
Xmas service in 1480 Suceava must've had Bulgarian liturgy, Byzantine religious music & maybe Romanian carols sung at the end (or outside the church) with smell of fresh sweet bread (cozonaci) & pork products. probably no "sarmale" yet...
@Purpura57912934

@Purpura57912934
"cozonac" not sure either, it's a Greek origin word. was that a thing in Byzantium? @ArcGreek
the pork related vocabulary is mostly Latin, it sounds it was a thing practiced all along as was the vining, apiculture. Wine, honey are items frequently mentioned in those documents.
the pork related vocabulary is mostly Latin, it sounds it was a thing practiced all along as was the vining, apiculture. Wine, honey are items frequently mentioned in those documents.