The parties switched platforms.
I don't know you well enough to know if you are typing that ridiculous sentence sarcastically or not, but the troubling thing about that myth is that it's so comforting to several different groups.
It is a nice comforting narrative to modern-day liberal Democrats, as (in their minds) it absolves the party of any racism in its past, all the while stealing any Republican accomplishments on the matter and forking it right over to the endless, always-right social treadmill of "liberalism."
It's comforting to Black voters, as it completely justifies the demographic group's switch from the GOP to the Democrats. It's a lot more noble in the history books to paint it as the GOP turning on Black voters one day in a spat of coded racism than Blacks being forced to vote their economic interests three decades before the CRA/VRA.
It's also pretty comforting to Southern whites, as they can justify their ancestors' (whom they otherwise seem quite proud of) support of an openly racist party by hiding behind things like "states' rights" or "small government." Of course, things like the Dred Scott case show that Southern Democrats didn't give a crap about states' rights and were willing to take any avenue possible to preserve White racial supremacy.
That pretty much just leaves Northern Republicans and Democrats who are true students of history/not completely ignorant (which, I'll say, describes most on this forum) to try to refute this fairy tale and tell the much more complicated story.
The Democratic Party was openly hostile to blacks until the FDR years. This was, in no small part, because in the South, most states did not allow blacks to become memberes of the Democratic Party. This was not true in every state, but it was true in many, and the "White Primary" lasted until 1944 when the SCOTUS threw it out.
In truth, it was the Nixon years that drove blacks out of the GOP in any kind of significant numbers. Goldwater ran them off with his Civil Rights stances, but Nixon kept them gone with a Southern Strategy that sided against blacks whenever they were in conflict with the White South. As late as the mid-1960s, Everett Dirksen and Gerald Ford were producing GOP votes to ram home Civil Rights legislation, but this all stopped during the Nixon years.
