The Southern Strategy started with him not Goldwater or Nixon
IMO the earliest seeds of it go back to the 20s.
First GOP presidential campaign to actively try to appeal to Southern whites was 1896.
The Southern Strategy is always already
I said the 20s since the strength of the Lily-white movement in that particular era and Al Smith's poor performance seems like an obvious starting point for the shifts seen in the 30s.
Really, once Democrats were competitive with Black voters something like the Southern Strategy was probably inevitable.
Might be an interesting thread topic.