However, barbecue changed as much as the nation. After the abolishment of slavery, many African-Americans in the southern states took part in what is now known to be the pre-curser to The Great Migration or the migration north by African American families. It's here we begin to look at how barbecue changed throughout its journey in the United States. from the vinegar-based Carolinas, and Virginia variety, to the sweet-tasting, tomato-based sauce that's known in the Memphis Area and the Gulf Coast. These variants have set the stage for what has become one of the most heated arguments in American Cuisine.