Alright, well I didn't really take the time to surf the web to find the similarities, so I just googled the definitions and tried to form some kind of abstract conclusion. Mind you, this is by no means accurate or even logical, so take heed in my words.
Modernism - The deliberate departure from tradition and the use of innovative forms of expression that distinguish many styles in the arts and literature
Provincialism - a lack of sophistication
I think think the two are alike in the way of saying that deliberatly removing yourself from tradition to come up with an innovative form of expression could possibly show a lack of sophistication. Tradition in itself it pretty sophisticated, because there is so much to it and for someone to get away from that form of thinking shows simplicity.
Lol. I'll understand if this didn't make any sense to your what-so-ever, but I hope that it helped a little.
~Knows