Gygax and Perren's set of medieval miniatures rules from the Castle & Crusade Society newsletter The Domesday Book brought Gygax to the attention of Guidon Games, who hired him to produce a "Wargaming with Miniatures" series of games. Towards the end of 1970, Gygax worked with Don Lowry to develop the first three products for the new Guidon Games wargames line. Among the three was a pamphlet of medieval rules entitled Chainmail which adapted much of the medieval rules published in the Domesday Book. Late in the development process, Gygax added to the end of Chainmail fourteen pages of a "Fantasy Supplement" which detailed the behavior of Heroes, Wizards, dragons, elves and various other fantastic creatures and people. First edition Chainmail saw print in March 1971. It quickly became Guidon Games's biggest hit, selling one hundred copies per month. A second edition would follow in July 1972, with several expansions and revisions to the original game. The January 1972 issue of the International Wargamer initially published the most significant of these changes, including the splitting of the "Wizard" type into four distinct levels of spell casters. The cover artwork of a fighting Crusader was inspired by a Jack Coggins illustration from his book The Fighting Man: An Illustrated History of the World's Greatest Fighting Forces. Both Perrin and Gygax "swiped" Coggin's artwork to illustrate their preliminary articles about Chainmail that appeared in Panzerfaust and The Domesday Book. When Don Lowry of Guidon Games agreed to publish Chainmail, Lowry swiped the same Coggins illustration for the cover.
Rule systems
Chainmail effectively comprises four distinct wargame systems:
A set of mass-combat rules, heavily indebted to the medieval systems of Tony Bath and intended for a 20:1 figure scale. These developed from the Lake Geneva medieval system originally published in Panzerfaust and in Domesday Book #5. In these rules, each figure represents twenty men. Troops are divided into six basic types: light foot, heavy foot, armored foot, light horse, medium horse, and heavy horse. Melee is resolved by rolling six-sided dice: for example, when heavy horse is attacking light foot, the attacker is allowed to roll four dice per figure, with each five or six denoting a kill. On the other hand, when light foot is attacking heavy horse, the attacker is allowed only one die per four figures, with a six denoting a kill. Additional rules govern missile and artillery fire, movement and terrain, charging, fatigue, morale, and the taking of prisoners.
A set of man-to-man combat rules, ultimately deriving from a contribution to Domesday Book #7. Gygax lost the name of the contributor, and thus the rules were published anonymously. The core of these rules became the Appendix B chart mapping various weapon types to armor levels, and providing the needed to-hit rolls for a melee round. The man-to-man melee uses two six-sided dice to determine whether a kill is made.
A set of jousting rules, which derive from the Castle & Crusade Society jousting rules published in Domesday Book #6, and reprinted in Domesday Book #13. These rules were originally designed for postal play; members of the C&CS could participate in jousting tourneys in order to raise their standing in the Society. Dungeons & Dragons refers to jousting matches utilizing the Chainmail rules.
A set of fantasy combat rules. The core of these rules is the Appendix E chart showing the die rolls needed for various fantastic types to defeat one another in battle.
Fantasy supplement
Gygax wanted to capture the sort of swashbuckling action of Robert E. Howard's Conan the Barbarian books in a wargame. Shortly before the publication of Chainmail, Gygax wrote to Wargamer's Newsletter describing his intention to add "rules for Tolkien fantasy games" to his medieval miniatures rules, including rules for balrogs, hobbits, trolls, giants and dragons. The first edition Chainmail Fantasy Supplement added such concepts as elementals, magic swords, and archetypal spells such as "Fireball", "Lightning Bolt" and six other spells. Borrowing a concept from Tony Bath, some figure types may make saving throws to resist spell effects; a stronger wizard can cancel the spell of a weaker wizard by rolling a seven or higher with two six-sided dice. Creatures were divided between Law and Chaos, drawing on the alignment philosophies of Poul Anderson, as popularized by Michael Moorcock's Elric series. When fighting mundane units, each of the fantasy creatures is treated as one of the six basic troop types. For example, hobbits are treated as light foot and elves are treated as heavy foot. Heroes are treated as four heavy footmen, and require four simultaneous hits to kill; Super-Heroes are twice as powerful.
Use with ''Dungeons & Dragons''
In the July 1978 issue of The Dragon, Gary Gygax wrote that for the first two years of Dungeons & Dragons, players played primarily without the use of any miniature figures. If visual aids were needed, then the players would draw pictures, or use dice or tokens as placeholders. By 1976, there was a movement among players to add the use of miniatures to represent individual player characters.