Back in the early days of the Old School Revival, Delta's D&D Hotspot was a place to go for thoughtful design and scholarship, firmly rooted in the classic games and free of the edgy or curmudgeonly posing indulged elsewhere. Like many of that blogging generation, Delta (Daniel R. Collins) has put out books of his house rules, modifications and expansions of Original D&D, all in a familiar trade dress. One of these, revised in 2021, is a set of rules for miniatures battles in D&D campaigns, called Book of War.
OD&D itself had a mass combat supplement: Swords & Spells, authored by Gary Gygax in 1976, but little noticed by revivalists today. Still, its features clearly influenced the more widely known and promoted Battlesystem, and also Delta's battle rules for OD&D. All three share a 10 soldiers:1 figure scale with provision for lone heroes and leaders. All three, in different ways, scale unit stats to D&D individual stats. Command, movement, and morale, though handled in slightly different ways, follow a common model that was also not far from standard rules for formed historical battles. We can also see a preview of AD&D in the percentile morale approach and weapon-to-armor modifiying tables.
