Puzzle 1: Col. Edwin V. Sumner commands LTC Joe Johnston, majors John Sedgwick and Wm. H. Emory, and a Captain McClellan. This is the First Regiment of Cavalry. Excluding McClellan's time, this lineup served together from early 1855 to the end of 1860. McClellan resigned in 1857.
Puzzle 2: Col. A.S. Johnston commands LTC Robert E. Lee and majors Wm. Hardee and George Thomas. This team served together from March 1855 to March 1861 in the Second Regiment of Cavalry. Hardee left in mid-1860 after being seconded to the USMA for much of his cavalry assignment.
Commentary will follow.