What notorious organization was formed to exploit government contracts related to the Union Pacific Railroad?

The organization that was formed to exploit government contracts related to the Union Pacific Railroad was Credit Mobilier. This scandal emerged in the 1860s during the construction of the transcontinental railroad and involved a construction company that was set up as a front to siphon off profits from the railroad's federal contracts. The company created inflated bills for the work done, allowing its executives and investors to profit significantly at the expense of the government and taxpayers. The scandal was significant as it highlighted issues of corruption, cronyism, and the intertwining of business and politics during the Gilded Age, leading to a loss of public trust in government institutions.

The other organizations mentioned pertain to different contexts: the Whiskey Ring was involved in a liquor tax scandal during Grant's presidency; the Redeemers were a political coalition in the South after Reconstruction aimed at restoring white Democratic rule; and the Ku Klux Klan was a white supremacist group that emerged to intimidate and suppress African Americans and their allies during and after the Reconstruction era. These distinctions clarify the unique role that Credit Mobilier played in the realm of corruption related to railroad expansions.