After the Civil War, federal troops occupied the defeated South and helped enforce civil rights laws, enabling Republicans to win power in many Southern states thanks to the overwhelming votes of newly enfranchised black men. While they controlled many former rebel states during Reconstruction, other Southern states like Kentucky that hadn’t seceded stubbornly resisted the Republican Party. After Reconstruction ended and those troops withdrew, white-supremacist reactionary Democrats retook power in nearly every Southern state, and even the modern pro-civil rights party held every Southern state legislative chamber as recently as 1992.

While the two parties’ voter coalitions and their positions on civil rights have changed massively in the last century and a half, one thing remained constant: Republicans had never held every Southern legislature at once. That streak ended in 2016, when Republicans won control over the Kentucky state House for the first election since 1920, giving them control of both chambers at once there for the first time in state history. Democrats had lost power in Kentucky during part of the Civil War, when pro-Confederate forces tried to form a rival secessionist government, but it was to the Unionists instead of the Republicans.

With Kentucky, Republicans now control both legislative chambers in every Southern state, roughly those that span from the Virginias to Texas. Although the Census Bureau still defines the Democratic-controlled ex-slave states of Delaware and Maryland as Southern, their cultural affinities have drifted much closer to the Northeast in the post-World War II era. Donald Trump won all of these Southern states except Virginia, while Republicans have also aggressively gerrymandered the vast majority of their state legislatures. However, Kentucky’s lower chamber was a rare Democratic-drawn map, helping the party cling to power until 2016.