Brigadier General Thomas J. Wood From Wikipedia:
He suffered controversy at the
Battle of Chickamauga, where he was blamed for contributing to
William S. Rosecrans's defeat. On September 19, 1863, a breakdown in situational awareness by Rosecrans and poor staff work resulted in Wood receiving a seemingly senseless order that, if literally obeyed, required him to pull his division out of the line to the support of another division further to his left, dangerously creating an unprotected gap in the right of the line. Instead of verifying his commander's actual intent, Wood elected to regard the order as imperative and moved his division out of its position.
[1]
Historian Peter Cozzens wrote:
While Wood read the order, [Col.] Starling began to explain its intent. Wood interrupted. Brannan was in position, he said, there was no vacancy between Reynold's division and his own. "Then there is no order," retorted Starling. There the matter should have ended.
And with anyone but Tom Wood, it most assuredly would have. Rosecrans had upbraided Wood twice for failing to obey orders promptly. ...[including] the dressing down just 90 minutes earlier in front of Wood's entire staff. The barbs of Rosecrans's invective pained the Kentuckian. Anger clouded his reason. No, he told Starling, the order was imperative, he would move at once."[2]
Less than 30 minutes after Wood moved his division,
Confederate Lt. Gen. James Longstreet's men poured through the resulting gap and cut Rosecrans's army in two. Rosecrans was eventually relieved from command of the Army of the Cumberland following this Union defeat, while Wood retained his division.
Bonus Question: John Wilkes Booth wrote this in his diary.