Chancellorsville (61) was one of the first four hex-based wargames published in 1961 by Avalon Hill (the others are D-Day, Gettysburg(61) and Civil War). The game system, but not scale, is identical to Gettysburg(61). That system is the same as other early 60's AH board games with one major difference: artillery has a two-hex zone of control and is immune to non-artillery at range 2. This greatly complicates the details of game tactics compared to, say, D-Day or Waterloo.
The combat results table is one used for all early 60s Avalon Hill wargames (A or D Elim, A or D Back 2, Exchange; 3:1 odds needed to avoid the chance of complete attacker elimination). A significant difference in this and other post-61 AH games is that inexact odds round toward 1:1 (e.g., both 5:3 odds and 3:5 odds are resolved as 1:1).
Units are infantry and cavalry divisions (CSA can break down to brigades) and artillery brigades (USA) or battalions (CSA). Units have strength factor and movement factor. Both sides also have field fortification markers, deployed at the start of the game. The USA has boat and pontoon bridge units which aid in river crossing.
The game lasts 25 turns, turns being about 3 hours long during daylight and longer at night. The map depicts the Rappahannock/Rapidan river junction, an area containing the Wilderness, Chancellorsville, Fredericksburg and the south bank to the Potomac (about 20 x 25 miles), so the scale (at 1000 yds/hex) is not quite tactical. The map (like others of that year) was designed with mono-color hexes (woods, river, hills). That style has been criticized as artistically unappealing, but it is never ambiguous what terrain effects apply to a given hex.
The historical battle featured two brilliant flanking maneuvers, one initially by the USA which could have pocketed Lee’s army, and the second, Stonewall Jackson’s fatal flank march to attack and defeat the US XIC. The first is adequately depicted by pre-game set-up rules. The second, alas, is beyond this game system’s capacity due to perfect intelligence and command control (inherent in nearly all games of this period).
Victory conditions are determined solely by the number of surviving CSA units; 16 or more points surviving out of an initial 87 and he wins. Territory has no effect on victory.
Chancellorsville (61) was dropped form the AH line in 1964 and was not revived until 1974 with a similar scale game with significantly different rules and a slightly different map.
Postscript: There were (at least) two versions of the Instructions (rules) for the 1961 version of Chancellorsville, both copyright 1961. There was considerable rephrasing of the rules, but only one meaningful change, that related to fortress markers and advance after combat.
Description by E_T_Lee