A reactionary is someone who seeks to restore conditions to those of a previous era. A reactionary is sometimes described as an extreme conservative, but whereas a conservative seeks, in the simplest terms, to preserve the status quo, a reactionary seeks to return to the situation of a prior time. Thus a reactionary can be described as one who seeks to undo recent changes and thus turn the clock back.

In American history, many have argued that the Confederacy was inherently reactionary in its desire to prevent economic industrialization. Others see it as a conservative effort to adhere to original Constitutional norms. In either case, the American South has produced figures and movements that seem reactionary in retrospect. Among these are the literary and cultural critics known collectively as the Southern Agrarians along with their sympathizers. The most reactionary of these was perhaps Donald Davidson, who adhered to his agrarian beliefs long after many of the other members of the original group had ceased to embrace much of their original agenda.

After the publication of the so-called agrarian manifesto, I'll Take My Stand, in 1930, many of the contributors to that book published in the periodical The American Review. Published and edited by the fascist Seward Collins, The American Review served as a vehicle for further examination of agrarian and anti-modern proposals, including the distributism of G.K. Chesterton and Hilaire Belloc.

During the same period, other areas of America saw the rise of reactionary spokesmen. Father Charles Coughlin of Detroit won over a huge audience with his radio broadcasts, which were notable for their harsh criticism of the New Deal and their anti-Semitic charges against Jewish bankers.

The reactionary is considered to be the antithesis to the radical, though dramatically reversive change can itself be considered radical.