On 8 October 1862 Confederate and Union armies fought the Battle of Perryville, the largest battle of the Civil War in Kentucky1. It was tactically inconclusive, but it ended the Confederate invasion2 of the state: outnumbered, General Bragg withdrew to Tennessee, and Kentucky stayed in the Union.
On 8 October 1862 the American Civil War reached its high-water mark in Kentucky, when Confederate and Union armies collided in confusion near the small town of Perryville. It was the biggest battle ever fought in the state, and though it ended without a clear winner on the field, it decided the fate of Kentucky. This is how it happened.
Part of The greatest battles of the Civil War · Before: The Battle of Antietam · Next: The Battle of Fredericksburg
Bragg's invasion of Kentucky
In the late summer of 1862 the Confederacy went on the offensive in the west. General Braxton Bragg led his army north into Kentucky, hoping to win the border state for the South, draw recruits and threaten the Ohio River. For a time the campaign went well, and a Confederate government was even installed at Frankfort.3
Pursuing him was the Union Army of the Ohio under Don Carlos Buell. A severe drought had left the countryside parched, and as the armies manoeuvred, both were drawn toward the streams around Perryville in a desperate search for water. There, on 8 October, they stumbled into battle.
The acoustic shadow
Perryville is famous for one of the strangest quirks in military history. Thanks to the lie of the land and the wind, an acoustic shadow fell across the field: Buell, only a few miles away at his headquarters, could not hear the sound of the fighting1 and did not realise a major battle was under way.
As a result, most of his army, which heavily outnumbered the Confederates, stood idle through the afternoon while only part of it was engaged. Bragg, believing he faced only a fraction of the Union force, attacked hard.
The bloody afternoon
The Confederate assault fell on the Union left, held by the corps of Alexander McCook1, and drove it back more than a mile in savage fighting. For a few hours the Confederates had the better of the battle, overrunning batteries and breaking brigades.
But the sheer imbalance of numbers told. Union reinforcements stiffened the line, the attack lost momentum, and on another part of the field Union troops pushed into the town itself. By nightfall the fighting died away with neither side driven from the field, and some 7,600 men had fallen.1
Bragg withdraws
That night Bragg learned the truth he had not grasped during the battle: he had fought only a part of a Union army far larger than his own, and it would overwhelm him if he stayed. Rather than renew the fight, he ordered a retreat, pulling his army out of Kentucky and back into Tennessee.1
On the field itself Perryville had been a draw, even a Confederate tactical success. But by withdrawing, Bragg abandoned the whole campaign and the hope of winning Kentucky. A tactical stalemate had become a Union strategic victory.
Aftermath
With Bragg's retreat, Kentucky was secured for the Union for the rest of the war, a serious blow to Confederate hopes in the west. It was one of the bloodiest battles of the western theatre for the numbers actually engaged.
Buell was widely criticised for failing to hear the battle and for not pursuing Bragg vigorously, and he was soon replaced by William Rosecrans.4 Bragg's retreat, meanwhile, deepened the distrust of him among his own officers that would dog the Confederate army of the west for the rest of the war. Compare the great clashes of the conflict in the greatest battles of the Civil War.