I am going to disagree with the last statement. 140 years ago, the Republicans were the liberals, and the Democrats were the conservatives. One of the most conservative presidents this country ever had was Grover Cleveland. The New Deal effectively changed that, as what had been a party made up almost entirely of the South, suddenly became a party that the rest of the nation was drawn to, and of course, they immediately showed their anti Southern bias, and they drove the South away.
The Republican Party, as it were, almost had died away by the 1950’s, the only thing that saved it was the fact that the Democrats, which by this point were run by the same liberals who ran the Republican Party between Reconstruction and the New Deal, pushed Southerners out, and the Southerners came to the Republican Party, where there was Barry Goldwater, who had many of the same values regarding federal authority that the old Bourbons had in the 1870’s when they helped liberate the region from Yankee rule.
And look at the map today, without the South, there would be no Republican Party, we are the base, or as I told my daughter when she asked me the predictable question about the parties, I told her “they switched”, and that’s what happens. The Democrats that are in the South today are the ideological descendants of the Populists, and the Republicans in the south are the descedants of the Bourbons. Or to put it another way, Democratic legislators voted to change the Georgia state flag, Republican legislators voted to keep it. Soon after this, Georgia elected it’s first Republican legislature in 130 years.
The parties switched, and as my final note, the war had nothing to do with slavery.
I’m going to take issue with your assessment. It’s far more complex than that, and some is just a bit off-base.
Both parties had large groups of liberals and Conservatives, but a 19th century liberal would be quite Conservative today (even some 1950s “liberals”, for that matter — JFK, for example). Only in the last 30+ years have those ideological groups firmly attached themselves to one party or another.
Briefly on Cleveland, he was a Conservative, but he was replaced by the liberal William Jennings Bryan in 1896 (though Bryan’s social views today would be to the right of most Conservative Republicans).
RE: Georgia. The Republican party in the state was not built upon the backs of old-time Bourbonism, that’s just plain wrong. Most of the seeds were planted by Northern immigrants since the 1950s (Gingrich was from PA; Bob Barr and Paul Coverdell were from Iowa; John Linder from Minnesota) that brought their Republicanism with them. The old Dixiecrats died off, and not a one of them became a Republican (aside from Albert Watson & Thurmond in SC, for example). A generation or two ago, many of today’s Southern voting Republicans were Northerners, but those folks voted with their feet, the reason why once hyper-Republican states like Massachusetts or the NYC suburbs have gone the opposite way (with MA now as politically a one-party backwater as pre-1960s LA or MS).