- Meagher County -

Named for Gen. Thomas F. Meagher, then acting territorial governor. Formed on March 26, 1866 from a portion of Gallatin county by the second territorial assembly. All laws enacted by the 2nd assembly were nullified by Congress, but the law creating the county was re-enacted on 16 November 1867. Portions of Meagher county were later taken to form portions of Broadwater, Cascade, Fergus, Lewis and Clark, Sweet Grass, Wheatland and Yellowstone counties.