His most famous service was defending "Hell's Half Acre" at the Battle of Stones River in 1862, and seizing Fort McAllister, Georgia, in December 1864, which allowed William Sherman to capture Savannah at the end of his March to the Sea.

He spent his boyhood in the town of Hiram and formed a close personal friendship with future President James A. Garfield.

Before the Civil War, he served primarily in the Pacific Northwest and Texas, where he was wounded severely on November 3, 1859, during a fight with the Comanches along the Llano River.

His brigade was reorganized into the XIV Corps (later to be known as the Army of the Cumberland) under Maj. Gen. William S. Rosecrans, and, in this organization, Hazen served in his most famous engagement, the Battle of Stones River, at Murfreesboro, Tennessee.

During Sherman's March to the Sea, Hazen's division distinguished itself in the capture of Fort McAllister, Georgia, on December 13, 1864.

He served primarily on the Western frontier, including being stationed at Fort Buford in the Dakota Territory from 1872 to 1880, but he also visited Europe as an observer during the Franco-Prussian War.

Stanley, who was fighting other generals over credit for the Union victory at the Second Battle of Franklin, argued that the monument was in the wrong place.

Hazen's relationships with Custer and with his superiors in the post-war army were such that the writer Ambrose Bierce called him "The best hated man I ever knew".

On December 15, 1880, President Rutherford B. Hayes promoted Hazen to brigadier general and appointed him Chief Signal Officer of the U.S. Army, a post he held until his death.

[8] His tenure was noted for focusing his department on basic research, rather than the practical matters that occupied his predecessor, Albert J.

One of the duties of the U.S. Army Signal Corps at the time was the management of the Weather Service and Hazen criticized the government's lack of response to the distress of the International Polar Year expedition to Fort Conger, Lady Franklin Bay (on Ellesmere Island, Canada).

Hazen publicly criticized Secretary of War Robert Todd Lincoln for his handling of the affair, citing his refusal to send further assistance after the failure of Garlington's rescue mission, until Greely's wife, Henrietta, forced Lincoln to act in response to outraged public opinion.

Hazen died in Washington, D.C., having been taken ill after attending a reception held by President Grover Cleveland,[11] and is buried in Arlington National Cemetery.