‘Grits’ and ‘Hominy Grits’ can be considered different products. But it’s all corn (maize, maiz), so it’s native to Mexico.
(Our word ‘corn’ originally referred to just about any cereal grain, and began to be transferred to maize after the discovery of the New World.)
SoCal bred, so Mexican was second nature to us. Her grandmother was southern, but she knows little of her cooking unfortunately.
I am the Creole/Cajun chef, not that I know squat other than what I like to eat.