The southern democrats ruled the Old South before the Civil War, and it was the democrats who intimated black republicans, after the war. Is that also part of the southern history that should be forgotten as well?  It sounds like your "culture of institutionalized racism" came from your own party.  

 From Wikipedia on the Old South:

The "Old South" also refers to the tradition of Southerners voting the Democratic ticket. During the Reconstruction period after the Civil War, black people exercising their right to vote for the first time led to a Republican South until 1877, when southern Democrats returned to power due to intimidation of black voters and laws that suppressed civil rights. 

As more middle class and educated Republicans move to the south from other areas of the country and white support for segregation and racist policies subsided, the south began to shift to the Republican party starting with Nixon winning a few southern states in 1968.