What was a term to describe journalists who wrote exposes during the progressive era ?

Muckrakers

Explanation:

Muckrakers was the name given to journalists of the Progressive Era who wrote exposes that attacked leaders and institutions. Typically, the work they produced was meant to expose corruption and injustice. These journalists were prominent in the 1890s-1920s, and their main goal was to encourage social change.

it affected it because the kingdoms (with trade) slowly got richer and richer.