Obviously you are unfamiliar with the various and splendid dialects of North America.
But you are also unfamiliar with the various and splendid dialects of the UK.
See "Isle of Wight Words," H. &. R. Smith, 1881, a standard work on one of the UK dialects. "I be gwine zoo vast as I can" for example (I am going as fast as I can).
Gwine (earlier gwyn) was added to the Oxford English Dictionary in 1987.
Suggested reading- "Tom Cladpole's Jurney to Lunnun," (42) 1831, by R. Lower. An English classic, in Sussex dialect. "He said he must be gwyn."