Whenever an origin of Romanians discussion pops out between two people, one being Romanian, sometimes the other debater will state that only romanian historians actively believe the pure, unadulturated theory of dacian origin, mixed with roman and then some slavic influence. While the last two seem pretty clear, the first one is always "mm, are you sure? I don't think so. People say it's dubious". But I've never heard actual historians saying this, so I ask you guys. Who are our ancestors?
Well, the idea that modern Romanians aren't in part descended from the Dacians/Thracians is completely false if you ask me.
I believe this for two reasons:
Our language still has Dacian words. http://linguistics.byu.edu/classes/ling450ch/reports/romanian.html
There's clear evidence of continued habitation in Dacia after the Romans left. http://www.academia.edu/171310/Reflections_on_the_Immediate_Post-Roman_Phase_of_Three_Dacian_Cities_Napoca_Potaissa_and_Porolissum
In my mind the history of us Romanians goes a bit like this: After the Romans left, the majority of the population of Dacia consisted of Dacians (both Romanized Dacians and Free Dacians), but they were likely in a decreased number than what they had previously been. During the course of the next few centuries, various groups of peoples (e.g. the slavs, teutons) came and intermingled with the Dacian population. This likely included a large migration of a Romance speaking population from just south of the Danube (i.e. around modern Bulgaria).
A lot of Romanians don't like any theory involving migration when it comes to our origin, but I believe that the migration of a Romance-speaking population is fairly necessary when it comes to explaining our history. It does a lot with regards to explaining how Romanian is a Romance language and not a Dacian language. Additionally, it does a lot to explain the existance of languages such as Aromanian and Megleno-Romanian.
Here's the source for that last paragraph. http://www.friesian.com/decdenc2.htm