What is a "ring"? On the North and South: who killed Reconstruction

It was a scandal.

Explanation:

The Whisky Ring was a scandal that pertained to the evasion of taxes by whiskey distillers and distributors by paying bribes to government collectors and politicians. The scandal was which was exposed in 1874 costed the government millions of dollars and President Ulysses S. Grant's private secretary was also involved in the Whisky Ring scandal.