He was born in Detroit, Michigan, to Daniel Corby, an Irish immigrant, and his wife Elizabeth, a Canadian.

In 1853, he enrolled in the 10-year-old college of Notre Dame in South Bend, Indiana, and began study for the priesthood three years later.

Corby left his position at Notre Dame and joined the predominantly Catholic Irish Brigade in 1861.

[2] During the battle of Antietam he rode back and forth along the lines of the Brigade, while shouting absolution to the men, of whom 540 became casualties before the recall order was given.

Corby blessing the troops was depicted in the 1891 painting Absolution under Fire by Paul Wood,[4] and dramatized in the 1993 film Gettysburg.

Corby Hall at Notre Dame is named for him, and a copy of the Gettysburg statue stands outside the building.

Corby overcame the $200,000 fire loss and rebuilt the Main Building - which now stands with its "Golden Dome."