Ambrose Gwinnett Bierce was born on June 24, 1842 in the settlement of Horse Cave, Ohio. He was the tenth of thirteen children born to Marcus Aurelius and Laura Sherwood Bierce.

The Bierces moved to Indiana during Ambrose's childhood, settling in Warsaw and then Elkhart.

 
 

Bierce benefited a great deal from his father's farmhouse library, and late in life declared it to be his most important early educational influence.

Another early influence on Bierce was his uncle, General Lucius Verus Bierce of Akron, Ohio. Ambrose observed carefully the man's idealism, oratorical skills, public service, and social activism. All his life, Bierce held up the career of his uncle as a model for his own.

When about seventeen, Bierce enrolled at the Kentucky Military Institute. There he learned about military subjects and appears to have studied topographical engineering. He adapted well to military life and discipline.

He left the Institute on the eve of the Civil War, returning to Indiana in 1860.