Statistics for occurrence #1 of “Chancellorsville” in chapter 7, page 214 of The Photographic History of The Civil War: in ten volumes, Thousands of Scenes Photographed 1861-65, with Text by many Special Authorities, Volume 10: The Armies and the Leaders.:
...early days contained about twelve thousand men. The command was given to Major-General J. F. K. Mansfield, who was killed at Antietam, the first battle of the new corps.
Its next battle was that of Chancellorsville where, with the Third, it bore the real brunt of the fight.
After Gettysburg, in which we remember the Twelfth by its gallant defense of Culps' Hill, it went with Hooker to Tennessee where one divi...
† This entity has been selected by the automated classifier as the most likely match in this context. It may or may not be the correct match.