It's a fact that many if not most of the early adopters of D&D, and even many of the AD&D "first generation" players were wargamers. I certainly was, and the progression from moving cardboard armored divisions around a hex-covered map to designing dungeons and playing half-elven magic-user/thieves was a direct one.
Nowhere is the overlap between hex-and-counter wargaming and role-playing (at least, as that overlap existed back in the late 1970's and early 1980's) clearer than in the several direct crossover products that brought the two sub-genres together.
It was, in essence, a tactical hex-and-counter wargame set in the City-State campaign, to be used to adjudicate large-scale battles therein without recourse to miniatures wargaming (which was in itself represented by products such as Sword & Spells, which was a supplement to the LBB's and, of course, Battlesystem). In addition to the various counters representing dwarf bowmen, high level warrior characters, cataphracts, etc., there are two very generic maps representing a hill position and an open field with some woods thrown on for variety. There is, of course, a counter given for a triceratops (if you look at the quite striking box cover, you'll see why; I would like to think the cover of the original Battlesystem box was an homage to that image).
There are eight historical scenarios presented (in which one, naturally, doesn't make use of the dwarf archers). However, for those interested in the Judges Guild campaign setting, there are three different scenarios presented which are set in the campaign, involving either the Invincible Overlord or the World "Emporer" [sic-- this typo is made more than once, including on the back cover advertising blurb!], as well as tables of organization for the armies of both powers.
There's also a very interesting reference to the "Decatur Fantasy Campaign World" as the setting for one battle scenario, but that's something I've never actually heard of. Google is of no help-- anyone have any info on this?
The rules for combat take up only 7 pages and are relatively straightforward, covering movement, facing (itself a holdover from the miniatures wargaming roots of hex-and-counter wargames), morale, stacking, line of sight, and of course combat. What is of particular interest is the inclusion of three and a half pages dedicated to "mustering an army". Here we have for troop maintenance costs, effectiveness of advertising for recruits, types of soldiers who respond, and so forth. Fans of 0E might want to grab a copy of the rules if nothing else, especially those interested in the now-current "Domain Game", because it gives some neat insights into what the state of the art was in this regard back in 1982 (doubly interesting is the fact that these rules were obviously written not with AD&D in mind, but with the LBBs, since it concerns itself with only three alignments.
The rules also have a page of tables dedicated to one of the questions that particularly vexes those who try to come up with mass combat rules for RPGs; what to do with PCs who aren't in command of the whole army?
"Often, the player-characters involved in a role-playing campaign are not in command of the entire army. It should also be noted that the number and type of counters present in this game are insufficient to represent an entire feudal or fantasy army. Future game releases will represent these additional troops and followers with counters of their own [ed. note: if only!]. The following charts should be consulted by the campaign Judge prior to each battle in which a player-character becomes involved if the player-character is not the leader of the fielded unit."What follows are charts to determine why the battle is happening in the first place, what the PC's unit's orders are, what (if anything) he is supposed to be defending or capturing, etc. Wonderful stuff.