Orwig's [Thomas G.] Artillery. See Pennsylvania Troops, 1st Regiment, Battery E.

Osborn's [Francis A.] Infantry. See Massachusetts Troops, 24th Regiment.

Osborne's [Wilbur F.] Heavy Artillery. See Connecticut Troops, 1st Regiment, Battery G.

Otis' [Elwell S.] Infantry. See New York Troops, 140th Regiment.

Otis' [John L.] Infantry. See Connecticut Troops, 10th Regiment.

Overton's [Edward, jr.] Infantry. See Pennsylvania Troops, 50th Regiment.

Parker's [Frank W.] Infantry. See New Hampshire Troops, 4th Regiment.

Parkhurst's [Veranus P.] Infantry. See Massachusetts Troops, 25th Regiment.

Parsons' [Augustin N.] Artillery. See New Jersey Troops, 1st Battery.

Patten's [Henry L.] Infantry. See Massachusetts Troops, 20th Regiment.

Patterson's [Henry D.] Heavy Artillery. See Connecticut Troops, 1st Regiment, Battery A.

Patterson's [Joab N.] Infantry. See New Hampshire Troops, 2nd Regiment.

Patton's [Alexander G.] Cavalry. See New York Troops, 7th Regiment.

Patton's [William] Cavalry. See Indiana Troops, 3rd Regiment.

Pearson's [Alfred L.] Infantry. See Pennsylvania Troops, 155th Regiment.

Peirson's [Charles L.] Infantry. See Massachusetts Troops, 39th Regiment.

Pendrell's [William] Heavy Artillery. See New York Troops, 13th Regiment, Batteries A and H.

Penfield's [Nelson] Infantry. See New York Troops, 125th Regiment.

Peninsula Artillery. See Virginia Troops.

Pennington's [Alexander C. M.,jr.] Artillery. See Union Troops, Regulars, 2nd Regiment, Battery M.

Pentecost's [Joseph H.] Infantry. See Pennsylvania Troops, 100th Regiment.

Perkins' [Joseph G.] Infantry. See Union Troops, Colored, 19th Regiment.

Perrin's [Walter S.] Artillery. See Rhode Island Troops, 1st Regiment, Battery A.

Perry's [Clinton] Sharpshooters. See New York Troops, 1st Battalion.

Pettes' [William H.] Engineers. See New York Troops, 50th Regiment.

Phillips' [Charles A.] Artillery. See Massachusetts Troops, 5th [E] Battery.

Phillips' [Charles B.] Infantry. See Ohio Troops, 130th Regiment.

Phillips' [John W.] Cavalry. See Pennsylvania Troops, 18th Regiment.

Phillips Legion. See Georgia Troops.

Pickering's [John,jr.] Heavy Artillery. See Massachusetts Troops, 13th Unattached Company.

Pier's [Colwert K.] Infantry. See Wisconsin Troops, 38th Regiment.

Pierce's [Henry H.] Heavy Artillery. See Connecticut Troops, 1st Regiment, Battery C.

Plaisted's [Harris M.] Infantry. See Maine Troops, 11th Regiment.

Pleasants' [Henry] Infantry. See Pennsylvania Troops, 48th Regiment.

Plimpton's [Josiah I.] Infantry. See New Hampshire Troops, 3rd Regiment.

Poor's [Walter S.] Infantry. See North Carolina Troops, Union, 2nd Regiment.

Powell's [Edward H.] Infantry. See Union Troops, Colored, 10th Regiment.

Pratt's [Franklin A.] Heavy Artillery. See Connecticut Troops, 1st Regiment, Battery M.

Prey's [Gilbert G.] Infantry. See New York Troops, 104th Regiment.

Price's [Isaiah] Infantry. See Pennsylvania Troops, 97th Regiment.

Pruyn's [Minott A.] Cavalry. See New York Troops, 7th Regiment.

Pulford's [John] Infantry. See Michigan Troops, 5th Regiment.

Purington's [George A.] Cavalry. See Ohio Troops, 2nd Regiment.

Purnell Legion, Infantry. See Maryland Troops, Union.

Ramsey's [David M.] Infantry. See Pennsylvania Troops, 101st Regiment.

Ramsey's [Joseph F.] Infantry. See Pennsylvania Troops, 187th Regiment.

Randol's [Alanson M.] Artillery. See Union Troops, Regulars, 1st Regiment, Batteries H and I.

Ransom's [Alfred] Artillery. See New York Troops, 23rd Battery.