DragonLancer
Hero
When 9 year old me was introduced to the idea of D&D in the early 80s, it was always billed as a medieval fantasy and that is how I view it even. I like the concept of castles and kings, knights in plate facing dragons and monsters...etc. Modern fantasy and D&D doesn't fit that anymore but I continue to play it as such.For those that do*, why do you prefer a medieval fantasy milieu for your D&D games? Why do you want castles and kings and thatch roofed villages, knights and towers and chain? Why do you not want firearms or printing presses, trains or airships?
D&D isn't perfect though. It's part medieval with knights and castles, part renascence, part pirates of the Caribbean and it's a weird hodgepodge but it works. Once you introduce even airships it becomes something else entirely and I hate the idea of magic as technology (one reason why I never got into Eberron). It's not medieval fantasy once you do that. I don't like firearms but since we tend to include galleons which have canons (again, that weird but workable hodgepodge) I can accept that up to a point but it does remove some of that medieval fantasy for me.
Lord of the Rings, King Arthur, Conan, Tarzan, 3 Musketeers.
Lord of the Rings, the films especially, are what I see a D&D version of medieval fantasy looks like. It's not our Euro-centric medieval but it carries that fantasy vibe the right way. The Arthurian legends are a great source of inspiration too. Conan while not medieval is the prime concept of the D&D Barbarian and that is why it works into the setting.