I also would like to know if it relates to any dialect.
A: またそんなことでこそこそやってるのか。
B: なんせ 我々にとっては重大{じゅうだい}問題{もんだい}でやんして...
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Sign up to join this communityI also would like to know if it relates to any dialect.
A: またそんなことでこそこそやってるのか。
B: なんせ 我々にとっては重大{じゅうだい}問題{もんだい}でやんして...
Yes, it is a dialect, and it is an old one. A quick equivalency would be:
でやんす = で ございます
でやんして = で ございまして
我々にとっては重大問題でやんして = 我々にとっては重大問題でございまして
Here's a good description from the home page of Sano city, Gifu prefecture which digs a bit into the grammar of it. Since it's on the city's site as an introduction of the regional culture, I imagine it is done by proper authority of the field, so I would defer the technical aspects of it to this page.