big foot country, n. — Green’s Dictionary of Slang

big foot country n.

[? the population ‘walks tall’; note legendary ‘Bigfoot’, a monstrous creature allegedly found in California]

(US black) the southern United States.

1967		C. Cooper Jr Farm (1968) 104: A little whitey came in from 1 of the deep bigfoot countries, a doctor.
1979		‘Iceberg Slim’ Airtight Willie and Me 13: You’re a champ chump from the Big Foot Country (deep South).