At the dawn of roleplaying, the Castle & Crusade Society and Lake Geneva Tactical Studies Association (LGTSA) focused on Medieval Britain, and produced the Chainmail tabletop wargame rules with a fantasy supplement, which in turn spawned the original Dungeons & Dragons game.
Design choices indicate that the focus was historical. Consider pole arms, extensively described in OD&D supplements and AD&D 1e, all of which inflict the same damage but which are individually specific to certain nationalities.
Was D&D originally intended to be an historical wargame with certain fantasy additions, roleplaying optional? (Bonus: Cite specific historical/wargame bits which were included.)