"Didn't the Republican party replace the Whigs who liked King George in the first place?."

I assume you're kidding, but in case you're not, your American history is bass ackwards. The Colonial Whigs were quite anti-King George. The American Whig part was extant about twenty years, fading away after the election of 1856, sundered by the issue of slavery, never to run a presidential candidate again. The Republicans filled the void and offered A. Lincoln as their first presidential candidate in 1860. He won.