Definitely German (west or western makes no difference).
I think I may have uneartehd a long standing mystery last week when I found a moss green brandy glass in ultrathin sodaglass - same type as discussed here - with an IG/ Ingridsticker on it, the florist supplier from Germany.
Question is, of course, where did THEY have it made - but there is undenyably some progress.
So your blue vase is most likely German, and quite possibly from Ingridglas.