Michael Corcoran was born in Carrowkeel, County Donegal, Ireland, September 21, 1827. The son of an officer in the British army, he received a good education, and at the age of eighteen was appointed in the Irish constabulary. The repressive measures taken by the organization against his countrymen impelled him to resign his commission in 1849 and to emigrate to the United States. He settled in New York and obtained a clerkship, first in the post office and later in the city register's office. Entering the 69th New York Militia as a private, he rose to colonel. Upon the occasion of the visit of the Prince of Wales (later Edward VII) in 1860, Corcoran refused to parade his regiment in the Prince's honor. For this insubordination he was court-martialed, and his trial was still pending at the outbreak of the Civil War, when the charges were dismissed to permit him to bring his command to the defense of Washington. The 69th Militia, which was not mustered into Federal service, fought at the battle of Manassas (Bull Run) in W. T. Sherman's brigade and here Colonel Corcoran was wounded and captured. Corcoran became a pawn in a game played by the Union and Confederate authorities: he was reserved for reprisal in the event of the execution of the crews of captured privateers by United States authorities. After being shuttled back and forth between a number of Confederate prison camps, Corcoran was exchanged in August, 1862, and was promoted to brigadier general of volunteers to rank from the date of the battle of Manassas the previous year. In the spring of 1863, while commanding a division of three brigades in the army of North Carolina, he took part in the Suffolk campaign in southeastern Virginia. Shortly after the battle of Gettysburg, General Corcoran and his brigade, "The Irish Legion," were transferred to the Department of Washington and assigned to Rufus King's division; Corcoran succeeded to command of the division in October. On December 22, 1863, while riding in the company of General Thomas Meagher near Fairfax Court House, Virginia, where his division was in winter quarters, Corcoran's horse fell, killing him. He was buried in Calvary Cemetery, Long Island City, New York.
Reference: Generals in Blue. Lives of the Union Commanders by Ezra J. Warner. Louisiana State University Press. Baton Rouge.