Green’s Dictionary of Slang

a euph. for damned adj.

1903		J. Furphy Such is Life 283: Lis’n him now, laughin’ fit to break his neck at some of his own gosh foolishness.
1915		H.L. Wilson Ruggles of Red Gap (1917) 98: Calls her ‘Maw’ all right now [...] but when that begoshed husband of hers is around the house she calls her ‘Mater’.
1920		Oklahoma Miner 12 Aug. 5/3: And b’gashed if he didn’t stop and cuss me.