No political party remains fixed. The Democratic Party's changes since its inception are as dramatic as any institution's, and studies since V.O. Key's Southern Politics in State & Nation (Knoxville, TN: University of Tennessee Press, 1984) have examined its evolution, but the rapid transformation of the Republican Party from the twentieth century to the twenty-first century is not as well studied. In The Transformation of The Republican Party, Jeffrey M. Stonecash documents and explains the process by which the GOP went from Roosevelt's opposition to the geographically, demographically, and philosophically different coalition of the 2020s, led by President Donald Trump. The task is sweeping and difficult, given the distinction between the party of the New Deal era and the party of Trump. In response to Roosevelt, the Republican Party organized around opposition to an expanded role for the federal government and a welfare state. Today, the GOP consists of an unusual coalition built around policies ranging from religious and social conservatism to business deregulation to Trump-era trade and immigration restrictions, which only scratches the surface of the upheavals over less than a century. That begs two questions. First, what are the critical steps that led from the GOP of the mid-twentieth century to the modern Republican Party; and