Cornelius Hedges was born in Westfield, Massachusetts, October 28, 1831, the son of Dennis and Alvina Hedges. He attended Yale, receiving his A.B. in 1853 and his A.M. in 1855. He also attended Harvard Law School and was admitted to the bar of the Commonwealth of Massachusetts. In 1856, soon after his marriage to Edna Layette Smith of Southington, Connecticut, he moved to Independence, Iowa, where he practiced law and published and edited the Independence Civilian. In April 1864, Hedges set out, on foot, for the gold mines of Montana. He arrived at Virginia City in the late summer and placer mined there and at Highland Gulch until January, 1865, when he moved to Helena and the newer diggings at Last Chance Gulch. Here, he was employed with both mining and the law. Hedges returned to the "States" in the summer of 1866 to purchase a five-stamp mill for the operations of his partner, George Wood, and himself, and to bring his family back to Montana. He and his family resided in Helena thereafter, while he continued practicing law, speculating in mining claims, and working as a public servant.

His public and political services were many and varied. He was U.S. District Attorney for Montana Territory in 1871, first Territorial Delegate to Congress in 1874, a member of the 1884 Constitutional Convention, a State Senator from 1889-1893, the Republican Caucus nominee for U.S. Senator, 1899, and Secretary of the State Board of Sheep Commissioners, 1897-1906. For many years, Hedges was also an editorial writer for the Helena Herald, a charter member of the Montana Bar Association, and a member and president of both the Montana Historical Society and the Montana Society of Pioneers. He was a founder and lifelong supporter of the Helena Public Library. Cornelius Hedges had been a Mason since 1857 and was one of the founders of the first Masonic lodge in Montana. He was known, during his lifetime, as the "Father of Montana Masonry." As a Mason, Hedges held the office of grand secretary of the Montana Lodge from 1872 until just prior to his death. His broad interests also led him to join the Washburn Expedition of 1870, which explored and publicized the Yellowstone area. During the return from Yellowstone, it was Hedges who suggested the preservation of the area as a national park. In the subsequent two years, he was active in the movement to create the park, which was achieved in 1872. In 1903, he was an honored guest at the cornerstone laying ceremony for the large arch at the park entrance. Hedges died in Helena, April 29, 1907.