What accounts for the rise of Progressivism at the turn of the twentieth century?

A lot of the impetus behind the Progressive movement came from people who represented the old Protestant elite. They were afraid of the loss of their power to upstarts, including self-made men such as Andrew Carnegie, who were not from this elite class. They were also fearful of the loss of what they considered a lack of competition in the business world. The so-called "robber barons" of the Gilded Age had cornered different markets so thoroughly that they had made these markets impervious to any competition. The Progressive movement was in some ways an attempt to open up these markets to competition through anti-trust regulations. In addition, the leaders of the Progressive movement sought to reform and remake immigrants and people of different cultures and religions. They feared that the great tide of immigrants at the turn of the twentieth century—who were mainly from Southern and Eastern Europe and who included Catholics and Jews—would overturn their cherished values. For example, the settlement movement attempted to inculcate into new immigrants the importance of cleanliness—an old Protestant value. The change in the business world and the changing nature of immigration gave rise to the Progressive movement.