This has got to be Major John Sedgwick, US Civil war general.
General John Sedgwick was serving as a Union commander in the U.S. Civil War, and was hit by sniper fire, at the battle of Spotsylvania, on May 9, 1864.
His corps was probing skirmish lines ahead of the left flank of Confederate defenses and he was directing artillery placements. Confederate sharpshooters were about 1,000 yards away.
He was the highest ranking Union casualty (the most senior by date of rank of all major generals killed) of the Civil War.
Sedgwick's reputation was that of a solid, dependable, but relatively unaggressive general. Ulysses S. Grant characterized Sedgwick as one who "was never at fault when serious work was to be done" and he told his staff that the loss for him was worse than that of an entire division.