The brake bridge looks like a Cinelli bridge; sometimes these got engraved with a name (not necessarily Cinelli, but whoever built the frame), sometimes not. We used a lot of them at Trek, as did many custom and low-production builders, both here and in Europe. What's the thread on the bottom bracket? Italian thread increases the probability, but not certainty, that it was an Italian builder. More detail on the seat cluster, lugs, and fork crown might give a clue.