End to the Progressive Era?

Question

What ended the progressive era? Was it the return of the republicans?

Answer 1

Actually, one of the Progressive Era's leading advocates was Republican President Theodore Roosevelt. He later tried to start a third political party called the "Progressive Party" (often referred to as the Bull Moose party).
The "Progressive" moniker did not have any party affiliation. Anyone trying to reform society and government after the corrupt "Guilded Age" (circa 1870-1900, famous for its bribes and laissez-faire capitolism) was called Progressive.
True, the Progressive platform and reforms became strictly the domain of the Democratic Party after FDR (another Roosevelt) introduced his New Deal (a very Progressive agenda) and the Republicans embraced big business and the upper class.