Hillbilly and Redneck Both Come from Scotland
The word "hillbilly" is frequently used to disparage particular Southerners who are seen as lacking in culture. Similar usage of the term "redneck" is common. Due to their longevity, you've probably heard all the stereotypes. Since Beverly Hillbillies premiered in 1962, the concept has become firmly entrenched. Although both of these words appear to be used almost exclusively to make fun of a particular segment of the American people, they are both Scottish in origin.
Following a coup against the previous king, James II, William of Orange was anointed king of England, Ireland, and Scotland in 1669. James ran away while preparing an Irish counterinvasion. However, William's supporters were hiding and waiting in the hills. Because they backed William, a.k.a. Billy, they were known as "billyboys" at the time. Therefore, the hillbillies became hillbillies.
Many Scottish and Irish immigrants who arrived to America in the 1700s settled in the Appalachian Mountains, which are now the region where the word "hillbilly" is most frequently used. Rednecks supported the Scottish Presbyterian Church. They sported crimson scarves around their necks to stand out from the crowd. The Presbyterian rednecks, like their hillbilly counterparts, settled some of the south; the English had populated a large portion of the north. Even for their forefathers, the term "redneck" persisted.