South Midland and Southern U.S.
Examples from the Web for mought
"'Pears like ter me it mought be powerful public," Pete Swofford objected.The Raid of The Guerilla and Other Stories|Charles Egbert Craddock
He looked at me incredulously and inquired, “Say, what mought the cows do in such snow as that.”Through Scandinavia to Moscow|William Seymour Edwards
Dey mought hurt yo', honey, an' beat po' ole Sarah Angeline moughty considerable!'Oswald Langdon|Carson Jay Lee
Why, to speak de troof, massa, him not so berry well as mought be.The Short-story|William Patterson Atkinson
Iffen I could of had some help when I been sick, I mought not be so no account now.Slave Narratives: A Folk History of Slavery in the United States|Work Projects Administration